uBlock/src/js/resources/scriptlets.js

/*******************************************************************************

    uBlock Origin - a comprehensive, efficient content blocker
    Copyright (C) 2019-present Raymond Hill

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see {http://www.gnu.org/licenses/}.

    Home: https://github.com/gorhill/uBlock

*/

import './attribute.js';
import './href-sanitizer.js';
import './json-edit.js';
import './json-prune.js';
import './noeval.js';
import './object-prune.js';
import './prevent-innerHTML.js';
import './prevent-settimeout.js';
import './replace-argument.js';
import './spoof-css.js';

import {
    getExceptionTokenFn,
    getRandomTokenFn,
    matchObjectPropertiesFn,
    parsePropertiesToMatchFn,
} from './utils.js';
import { runAt, runAtHtmlElementFn } from './run-at.js';

import { getAllCookiesFn } from './cookie.js';
import { getAllLocalStorageFn } from './localstorage.js';
import { matchesStackTraceFn } from './stack-trace.js';
import { proxyApplyFn } from './proxy-apply.js';
import { registeredScriptlets } from './base.js';
import { safeSelf } from './safe-self.js';
import { validateConstantFn } from './set-constant.js';

// Externally added to the private namespace in which scriptlets execute.
/* global scriptletGlobals */

/* eslint no-prototype-builtins: 0 */

export const builtinScriptlets = registeredScriptlets;

/*******************************************************************************

    Helper functions
    
    These are meant to be used as dependencies to injectable scriptlets.

*******************************************************************************/

builtinScriptlets.push({
    name: 'should-debug.fn',
    fn: shouldDebug,
});
function shouldDebug(details) {
    if ( details instanceof Object === false ) { return false; }
    return scriptletGlobals.canDebug && details.debug;
}

/******************************************************************************/

// Reference:
// https://github.com/AdguardTeam/Scriptlets/blob/master/wiki/about-scriptlets.md#prevent-xhr
//
// Added `trusted` argument to allow for returning arbitrary text. Can only
// be used through scriptlets requiring trusted source.

builtinScriptlets.push({
    name: 'generate-content.fn',
    fn: generateContentFn,
    dependencies: [
        'safe-self.fn',
    ],
});
function generateContentFn(trusted, directive) {
    const safe = safeSelf();
    const randomize = len => {
        const chunks = [];
        let textSize = 0;
        do {
            const s = safe.Math_random().toString(36).slice(2);
            chunks.push(s);
            textSize += s.length;
        }
        while ( textSize < len );
        return chunks.join(' ').slice(0, len);
    };
    if ( directive === 'true' ) {
        return randomize(10);
    }
    if ( directive === 'emptyObj' ) {
        return '{}';
    }
    if ( directive === 'emptyArr' ) {
        return '[]';
    }
    if ( directive === 'emptyStr' ) {
        return '';
    }
    if ( directive.startsWith('length:') ) {
        const match = /^length:(\d+)(?:-(\d+))?$/.exec(directive);
        if ( match === null ) { return ''; }
        const min = parseInt(match[1], 10);
        const extent = safe.Math_max(parseInt(match[2], 10) || 0, min) - min;
        const len = safe.Math_min(min + extent * safe.Math_random(), 500000);
        return randomize(len | 0);
    }
    if ( directive.startsWith('war:') ) {
        if ( scriptletGlobals.warOrigin === undefined ) { return ''; }
        return new Promise(resolve => {
            const warOrigin = scriptletGlobals.warOrigin;
            const warName = directive.slice(4);
            const fullpath = [ warOrigin, '/', warName ];
            const warSecret = scriptletGlobals.warSecret;
            if ( warSecret !== undefined ) {
                fullpath.push('?secret=', warSecret);
            }
            const warXHR = new safe.XMLHttpRequest();
            warXHR.responseType = 'text';
            warXHR.onloadend = ev => {
                resolve(ev.target.responseText || '');
            };
            warXHR.open('GET', fullpath.join(''));
            warXHR.send();
        }).catch(( ) => '');
    }
    if ( trusted ) {
        return directive;
    }
    return '';
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'abort-current-script-core.fn',
    fn: abortCurrentScriptCore,
    dependencies: [
        'get-exception-token.fn',
        'safe-self.fn',
        'should-debug.fn',
    ],
});
// Issues to mind before changing anything:
//  https://github.com/uBlockOrigin/uBlock-issues/issues/2154
function abortCurrentScriptCore(
    target = '',
    needle = '',
    context = ''
) {
    if ( typeof target !== 'string' ) { return; }
    if ( target === '' ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('abort-current-script', target, needle, context);
    const reNeedle = safe.patternToRegex(needle);
    const reContext = safe.patternToRegex(context);
    const extraArgs = safe.getExtraArgs(Array.from(arguments), 3);
    const thisScript = document.currentScript;
    const chain = safe.String_split.call(target, '.');
    let owner = window;
    let prop;
    for (;;) {
        prop = chain.shift();
        if ( chain.length === 0 ) { break; }
        if ( prop in owner === false ) { break; }
        owner = owner[prop];
        if ( owner instanceof Object === false ) { return; }
    }
    let value;
    let desc = Object.getOwnPropertyDescriptor(owner, prop);
    if (
        desc instanceof Object === false ||
        desc.get instanceof Function === false
    ) {
        value = owner[prop];
        desc = undefined;
    }
    const debug = shouldDebug(extraArgs);
    const exceptionToken = getExceptionTokenFn();
    const scriptTexts = new WeakMap();
    const getScriptText = elem => {
        let text = elem.textContent;
        if ( text.trim() !== '' ) { return text; }
        if ( scriptTexts.has(elem) ) { return scriptTexts.get(elem); }
        const [ , mime, content ] =
            /^data:([^,]*),(.+)$/.exec(elem.src.trim()) ||
            [ '', '', '' ];
        try {
            switch ( true ) {
            case mime.endsWith(';base64'):
                text = self.atob(content);
                break;
            default:
                text = self.decodeURIComponent(content);
                break;
            }
        } catch {
        }
        scriptTexts.set(elem, text);
        return text;
    };
    const validate = ( ) => {
        const e = document.currentScript;
        if ( e instanceof HTMLScriptElement === false ) { return; }
        if ( e === thisScript ) { return; }
        if ( context !== '' && reContext.test(e.src) === false ) {
            // eslint-disable-next-line no-debugger
            if ( debug === 'nomatch' || debug === 'all' ) { debugger; }
            return;
        }
        if ( safe.logLevel > 1 && context !== '' ) {
            safe.uboLog(logPrefix, `Matched src\n${e.src}`);
        }
        const scriptText = getScriptText(e);
        if ( reNeedle.test(scriptText) === false ) {
            // eslint-disable-next-line no-debugger
            if ( debug === 'nomatch' || debug === 'all' ) { debugger; }
            return;
        }
        if ( safe.logLevel > 1 ) {
            safe.uboLog(logPrefix, `Matched text\n${scriptText}`);
        }
        // eslint-disable-next-line no-debugger
        if ( debug === 'match' || debug === 'all' ) { debugger; }
        safe.uboLog(logPrefix, 'Aborted');
        throw new ReferenceError(exceptionToken);
    };
    // eslint-disable-next-line no-debugger
    if ( debug === 'install' ) { debugger; }
    try {
        Object.defineProperty(owner, prop, {
            get: function() {
                validate();
                return desc instanceof Object
                    ? desc.get.call(owner)
                    : value;
            },
            set: function(a) {
                validate();
                if ( desc instanceof Object ) {
                    desc.set.call(owner, a);
                } else {
                    value = a;
                }
            }
        });
    } catch(ex) {
        safe.uboErr(logPrefix, `Error: ${ex}`);
    }
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'replace-node-text.fn',
    fn: replaceNodeTextFn,
    dependencies: [
        'get-random-token.fn',
        'run-at.fn',
        'safe-self.fn',
    ],
});
function replaceNodeTextFn(
    nodeName = '',
    pattern = '',
    replacement = ''
) {
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('replace-node-text.fn', ...Array.from(arguments));
    const reNodeName = safe.patternToRegex(nodeName, 'i', true);
    const rePattern = safe.patternToRegex(pattern, 'gms');
    const extraArgs = safe.getExtraArgs(Array.from(arguments), 3);
    const reIncludes = extraArgs.includes || extraArgs.condition
        ? safe.patternToRegex(extraArgs.includes || extraArgs.condition, 'ms')
        : null;
    const reExcludes = extraArgs.excludes
        ? safe.patternToRegex(extraArgs.excludes, 'ms')
        : null;
    const stop = (takeRecord = true) => {
        if ( takeRecord ) {
            handleMutations(observer.takeRecords());
        }
        observer.disconnect();
        if ( safe.logLevel > 1 ) {
            safe.uboLog(logPrefix, 'Quitting');
        }
    };
    const textContentFactory = (( ) => {
        const out = { createScript: s => s };
        const { trustedTypes: tt } = self;
        if ( tt instanceof Object ) {
            if ( typeof tt.getPropertyType === 'function' ) {
                if ( tt.getPropertyType('script', 'textContent') === 'TrustedScript' ) {
                    return tt.createPolicy(getRandomTokenFn(), out);
                }
            }
        }
        return out;
    })();
    let sedCount = extraArgs.sedCount || 0;
    const handleNode = node => {
        const before = node.textContent;
        if ( reIncludes ) {
            reIncludes.lastIndex = 0;
            if ( safe.RegExp_test.call(reIncludes, before) === false ) { return true; }
        }
        if ( reExcludes ) {
            reExcludes.lastIndex = 0;
            if ( safe.RegExp_test.call(reExcludes, before) ) { return true; }
        }
        rePattern.lastIndex = 0;
        if ( safe.RegExp_test.call(rePattern, before) === false ) { return true; }
        rePattern.lastIndex = 0;
        const after = pattern !== ''
            ? before.replace(rePattern, replacement)
            : replacement;
        node.textContent = node.nodeName === 'SCRIPT'
            ? textContentFactory.createScript(after)
            : after;
        if ( safe.logLevel > 1 ) {
            safe.uboLog(logPrefix, `Text before:\n${before.trim()}`);
        }
        safe.uboLog(logPrefix, `Text after:\n${after.trim()}`);
        return sedCount === 0 || (sedCount -= 1) !== 0;
    };
    const handleMutations = mutations => {
        for ( const mutation of mutations ) {
            for ( const node of mutation.addedNodes ) {
                if ( reNodeName.test(node.nodeName) === false ) { continue; }
                if ( handleNode(node) ) { continue; }
                stop(false); return;
            }
        }
    };
    const observer = new MutationObserver(handleMutations);
    observer.observe(document, { childList: true, subtree: true });
    if ( document.documentElement ) {
        const treeWalker = document.createTreeWalker(
            document.documentElement,
            NodeFilter.SHOW_ELEMENT | NodeFilter.SHOW_TEXT
        );
        let count = 0;
        for (;;) {
            const node = treeWalker.nextNode();
            count += 1;
            if ( node === null ) { break; }
            if ( reNodeName.test(node.nodeName) === false ) { continue; }
            if ( node === document.currentScript ) { continue; }
            if ( handleNode(node) ) { continue; }
            stop(); break;
        }
        safe.uboLog(logPrefix, `${count} nodes present before installing mutation observer`);
    }
    if ( extraArgs.stay ) { return; }
    runAt(( ) => {
        const quitAfter = extraArgs.quitAfter || 0;
        if ( quitAfter !== 0 ) {
            setTimeout(( ) => { stop(); }, quitAfter);
        } else {
            stop();
        }
    }, 'interactive');
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'replace-fetch-response.fn',
    fn: replaceFetchResponseFn,
    dependencies: [
        'match-object-properties.fn',
        'parse-properties-to-match.fn',
        'safe-self.fn',
    ],
});
function replaceFetchResponseFn(
    trusted = false,
    pattern = '',
    replacement = '',
    propsToMatch = ''
) {
    if ( trusted !== true ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('replace-fetch-response', pattern, replacement, propsToMatch);
    if ( pattern === '*' ) { pattern = '.*'; }
    const rePattern = safe.patternToRegex(pattern);
    const propNeedles = parsePropertiesToMatchFn(propsToMatch, 'url');
    const extraArgs = safe.getExtraArgs(Array.from(arguments), 4);
    const reIncludes = extraArgs.includes ? safe.patternToRegex(extraArgs.includes) : null;
    self.fetch = new Proxy(self.fetch, {
        apply: function(target, thisArg, args) {
            const fetchPromise = Reflect.apply(target, thisArg, args);
            if ( pattern === '' ) { return fetchPromise; }
            if ( propNeedles.size !== 0 ) {
                const objs = [ args[0] instanceof Object ? args[0] : { url: args[0] } ];
                if ( objs[0] instanceof Request ) {
                    try {
                        objs[0] = safe.Request_clone.call(objs[0]);
                    }
                    catch(ex) {
                        safe.uboErr(logPrefix, ex);
                    }
                }
                if ( args[1] instanceof Object ) {
                    objs.push(args[1]);
                }
                const matched = matchObjectPropertiesFn(propNeedles, ...objs);
                if ( matched === undefined ) { return fetchPromise; }
                if ( safe.logLevel > 1 ) {
                    safe.uboLog(logPrefix, `Matched "propsToMatch":\n\t${matched.join('\n\t')}`);
                }
            }
            return fetchPromise.then(responseBefore => {
                const response = responseBefore.clone();
                return response.text().then(textBefore => {
                    if ( reIncludes && reIncludes.test(textBefore) === false ) {
                        return responseBefore;
                    }
                    const textAfter = textBefore.replace(rePattern, replacement);
                    if ( textAfter === textBefore ) { return responseBefore; }
                    safe.uboLog(logPrefix, 'Replaced');
                    const responseAfter = new Response(textAfter, {
                        status: responseBefore.status,
                        statusText: responseBefore.statusText,
                        headers: responseBefore.headers,
                    });
                    Object.defineProperties(responseAfter, {
                        ok: { value: responseBefore.ok },
                        redirected: { value: responseBefore.redirected },
                        type: { value: responseBefore.type },
                        url: { value: responseBefore.url },
                    });
                    return responseAfter;
                }).catch(reason => {
                    safe.uboErr(logPrefix, reason);
                    return responseBefore;
                });
            }).catch(reason => {
                safe.uboErr(logPrefix, reason);
                return fetchPromise;
            });
        }
    });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'prevent-xhr.fn',
    fn: preventXhrFn,
    dependencies: [
        'generate-content.fn',
        'match-object-properties.fn',
        'parse-properties-to-match.fn',
        'safe-self.fn',
    ],
});
function preventXhrFn(
    trusted = false,
    propsToMatch = '',
    directive = ''
) {
    if ( typeof propsToMatch !== 'string' ) { return; }
    const safe = safeSelf();
    const scriptletName = trusted ? 'trusted-prevent-xhr' : 'prevent-xhr';
    const logPrefix = safe.makeLogPrefix(scriptletName, propsToMatch, directive);
    const xhrInstances = new WeakMap();
    const propNeedles = parsePropertiesToMatchFn(propsToMatch, 'url');
    const warOrigin = scriptletGlobals.warOrigin;
    const safeDispatchEvent = (xhr, type) => {
        try {
            xhr.dispatchEvent(new Event(type));
        } catch {
        }
    };
    const XHRBefore = XMLHttpRequest.prototype;
    self.XMLHttpRequest = class extends self.XMLHttpRequest {
        open(method, url, ...args) {
            xhrInstances.delete(this);
            if ( warOrigin !== undefined && url.startsWith(warOrigin) ) {
                return super.open(method, url, ...args);
            }
            const haystack = { method, url };
            if ( propsToMatch === '' && directive === '' ) {
                safe.uboLog(logPrefix, `Called: ${safe.JSON_stringify(haystack, null, 2)}`);
                return super.open(method, url, ...args);
            }
            if ( matchObjectPropertiesFn(propNeedles, haystack) ) {
                const xhrDetails = Object.assign(haystack, {
                    xhr: this,
                    defer: args.length === 0 || !!args[0],
                    directive,
                    headers: {
                        'date': '',
                        'content-type': '',
                        'content-length': '',
                    },
                    url: haystack.url,
                    props: {
                        response: { value: '' },
                        responseText: { value: '' },
                        responseXML: { value: null },
                    },
                });
                xhrInstances.set(this, xhrDetails);
            }
            return super.open(method, url, ...args);
        }
        send(...args) {
            const xhrDetails = xhrInstances.get(this);
            if ( xhrDetails === undefined ) {
                return super.send(...args);
            }
            xhrDetails.headers['date'] = (new Date()).toUTCString();
            let xhrText = '';
            switch ( this.responseType ) {
            case 'arraybuffer':
                xhrDetails.props.response.value = new ArrayBuffer(0);
                xhrDetails.headers['content-type'] = 'application/octet-stream';
                break;
            case 'blob':
                xhrDetails.props.response.value = new Blob([]);
                xhrDetails.headers['content-type'] = 'application/octet-stream';
                break;
            case 'document': {
                const parser = new DOMParser();
                const doc = parser.parseFromString('', 'text/html');
                xhrDetails.props.response.value = doc;
                xhrDetails.props.responseXML.value = doc;
                xhrDetails.headers['content-type'] = 'text/html';
                break;
            }
            case 'json':
                xhrDetails.props.response.value = {};
                xhrDetails.props.responseText.value = '{}';
                xhrDetails.headers['content-type'] = 'application/json';
                break;
            default: {
                if ( directive === '' ) { break; }
                xhrText = generateContentFn(trusted, xhrDetails.directive);
                if ( xhrText instanceof Promise ) {
                    xhrText = xhrText.then(text => {
                        xhrDetails.props.response.value = text;
                        xhrDetails.props.responseText.value = text;
                    });
                } else {
                    xhrDetails.props.response.value = xhrText;
                    xhrDetails.props.responseText.value = xhrText;
                }
                xhrDetails.headers['content-type'] = 'text/plain';
                break;
            }
            }
            if ( xhrDetails.defer === false ) {
                xhrDetails.headers['content-length'] = `${xhrDetails.props.response.value}`.length;
                Object.defineProperties(xhrDetails.xhr, {
                    readyState: { value: 4 },
                    responseURL: { value: xhrDetails.url },
                    status: { value: 200 },
                    statusText: { value: 'OK' },
                });
                Object.defineProperties(xhrDetails.xhr, xhrDetails.props);
                return;
            }
            Promise.resolve(xhrText).then(( ) => xhrDetails).then(details => {
                Object.defineProperties(details.xhr, {
                    readyState: { value: 1, configurable: true },
                    responseURL: { value: xhrDetails.url },
                });
                safeDispatchEvent(details.xhr, 'readystatechange');
                return details;
            }).then(details => {
                xhrDetails.headers['content-length'] = `${details.props.response.value}`.length;
                Object.defineProperties(details.xhr, {
                    readyState: { value: 2, configurable: true },
                    status: { value: 200 },
                    statusText: { value: 'OK' },
                });
                safeDispatchEvent(details.xhr, 'readystatechange');
                return details;
            }).then(details => {
                Object.defineProperties(details.xhr, {
                    readyState: { value: 3, configurable: true },
                });
                Object.defineProperties(details.xhr, details.props);
                safeDispatchEvent(details.xhr, 'readystatechange');
                return details;
            }).then(details => {
                Object.defineProperties(details.xhr, {
                    readyState: { value: 4 },
                });
                safeDispatchEvent(details.xhr, 'readystatechange');
                safeDispatchEvent(details.xhr, 'load');
                safeDispatchEvent(details.xhr, 'loadend');
                safe.uboLog(logPrefix, `Prevented with response:\n${details.xhr.response}`);
            });
        }
        getResponseHeader(headerName) {
            const xhrDetails = xhrInstances.get(this);
            if ( xhrDetails === undefined || this.readyState < this.HEADERS_RECEIVED ) {
                return super.getResponseHeader(headerName);
            }
            const value = xhrDetails.headers[headerName.toLowerCase()];
            if ( value !== undefined && value !== '' ) { return value; }
            return null;
        }
        getAllResponseHeaders() {
            const xhrDetails = xhrInstances.get(this);
            if ( xhrDetails === undefined || this.readyState < this.HEADERS_RECEIVED ) {
                return super.getAllResponseHeaders();
            }
            const out = [];
            for ( const [ name, value ] of Object.entries(xhrDetails.headers) ) {
                if ( !value ) { continue; }
                out.push(`${name}: ${value}`);
            }
            if ( out.length !== 0 ) { out.push(''); }
            return out.join('\r\n');
        }
    };
    self.XMLHttpRequest.prototype.open.toString = function() {
        return XHRBefore.open.toString();
    };
    self.XMLHttpRequest.prototype.send.toString = function() {
        return XHRBefore.send.toString();
    };
    self.XMLHttpRequest.prototype.getResponseHeader.toString = function() {
        return XHRBefore.getResponseHeader.toString();
    };
    self.XMLHttpRequest.prototype.getAllResponseHeaders.toString = function() {
        return XHRBefore.getAllResponseHeaders.toString();
    };
}




/*******************************************************************************

    Injectable scriptlets

    These are meant to be used in the MAIN (webpage) execution world.

*******************************************************************************/

builtinScriptlets.push({
    name: 'abort-current-script.js',
    aliases: [
        'acs.js',
        'abort-current-inline-script.js',
        'acis.js',
    ],
    fn: abortCurrentScript,
    dependencies: [
        'abort-current-script-core.fn',
        'run-at-html-element.fn',
    ],
});
// Issues to mind before changing anything:
//  https://github.com/uBlockOrigin/uBlock-issues/issues/2154
function abortCurrentScript(...args) {
    runAtHtmlElementFn(( ) => {
        abortCurrentScriptCore(...args);
    });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'abort-on-property-read.js',
    aliases: [
        'aopr.js',
    ],
    fn: abortOnPropertyRead,
    dependencies: [
        'get-exception-token.fn',
        'safe-self.fn',
    ],
});
function abortOnPropertyRead(
    chain = ''
) {
    if ( typeof chain !== 'string' ) { return; }
    if ( chain === '' ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('abort-on-property-read', chain);
    const exceptionToken = getExceptionTokenFn();
    const abort = function() {
        safe.uboLog(logPrefix, 'Aborted');
        throw new ReferenceError(exceptionToken);
    };
    const makeProxy = function(owner, chain) {
        const pos = chain.indexOf('.');
        if ( pos === -1 ) {
            const desc = Object.getOwnPropertyDescriptor(owner, chain);
            if ( !desc || desc.get !== abort ) {
                Object.defineProperty(owner, chain, {
                    get: abort,
                    set: function(){}
                });
            }
            return;
        }
        const prop = chain.slice(0, pos);
        let v = owner[prop];
        chain = chain.slice(pos + 1);
        if ( v ) {
            makeProxy(v, chain);
            return;
        }
        const desc = Object.getOwnPropertyDescriptor(owner, prop);
        if ( desc && desc.set !== undefined ) { return; }
        Object.defineProperty(owner, prop, {
            get: function() { return v; },
            set: function(a) {
                v = a;
                if ( a instanceof Object ) {
                    makeProxy(a, chain);
                }
            }
        });
    };
    const owner = window;
    makeProxy(owner, chain);
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'abort-on-property-write.js',
    aliases: [
        'aopw.js',
    ],
    fn: abortOnPropertyWrite,
    dependencies: [
        'get-exception-token.fn',
        'safe-self.fn',
    ],
});
function abortOnPropertyWrite(
    prop = ''
) {
    if ( typeof prop !== 'string' ) { return; }
    if ( prop === '' ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('abort-on-property-write', prop);
    const exceptionToken = getExceptionTokenFn();
    let owner = window;
    for (;;) {
        const pos = prop.indexOf('.');
        if ( pos === -1 ) { break; }
        owner = owner[prop.slice(0, pos)];
        if ( owner instanceof Object === false ) { return; }
        prop = prop.slice(pos + 1);
    }
    delete owner[prop];
    Object.defineProperty(owner, prop, {
        set: function() {
            safe.uboLog(logPrefix, 'Aborted');
            throw new ReferenceError(exceptionToken);
        }
    });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'addEventListener-defuser.js',
    aliases: [
        'aeld.js',
        'prevent-addEventListener.js',
    ],
    fn: addEventListenerDefuser,
    dependencies: [
        'proxy-apply.fn',
        'run-at.fn',
        'safe-self.fn',
        'should-debug.fn',
    ],
});
// https://github.com/uBlockOrigin/uAssets/issues/9123#issuecomment-848255120
function addEventListenerDefuser(
    type = '',
    pattern = ''
) {
    const safe = safeSelf();
    const extraArgs = safe.getExtraArgs(Array.from(arguments), 2);
    const logPrefix = safe.makeLogPrefix('prevent-addEventListener', type, pattern);
    const reType = safe.patternToRegex(type, undefined, true);
    const rePattern = safe.patternToRegex(pattern);
    const debug = shouldDebug(extraArgs);
    const targetSelector = extraArgs.elements || undefined;
    const elementMatches = elem => {
        if ( targetSelector === 'window' ) { return elem === window; }
        if ( targetSelector === 'document' ) { return elem === document; }
        if ( elem && elem.matches && elem.matches(targetSelector) ) { return true; }
        const elems = Array.from(document.querySelectorAll(targetSelector));
        return elems.includes(elem);
    };
    const elementDetails = elem => {
        if ( elem instanceof Window ) { return 'window'; }
        if ( elem instanceof Document ) { return 'document'; }
        if ( elem instanceof Element === false ) { return '?'; }
        const parts = [];
        // https://github.com/uBlockOrigin/uAssets/discussions/17907#discussioncomment-9871079
        const id = String(elem.id);
        if ( id !== '' ) { parts.push(`#${CSS.escape(id)}`); }
        for ( let i = 0; i < elem.classList.length; i++ ) {
            parts.push(`.${CSS.escape(elem.classList.item(i))}`);
        }
        for ( let i = 0; i < elem.attributes.length; i++ ) {
            const attr = elem.attributes.item(i);
            if ( attr.name === 'id' ) { continue; }
            if ( attr.name === 'class' ) { continue; }
            parts.push(`[${CSS.escape(attr.name)}="${attr.value}"]`);
        }
        return parts.join('');
    };
    const shouldPrevent = (thisArg, type, handler) => {
        const matchesType = safe.RegExp_test.call(reType, type);
        const matchesHandler = safe.RegExp_test.call(rePattern, handler);
        const matchesEither = matchesType || matchesHandler;
        const matchesBoth = matchesType && matchesHandler;
        if ( debug === 1 && matchesBoth || debug === 2 && matchesEither ) {
            debugger; // eslint-disable-line no-debugger
        }
        if ( matchesBoth && targetSelector !== undefined ) {
            if ( elementMatches(thisArg) === false ) { return false; }
        }
        return matchesBoth;
    };
    const proxyFn = function(context) {
        const { callArgs, thisArg } = context;
        let t, h;
        try {
            t = String(callArgs[0]);
            if ( typeof callArgs[1] === 'function' ) {
                h = String(safe.Function_toString(callArgs[1]));
            } else if ( typeof callArgs[1] === 'object' && callArgs[1] !== null ) {
                if ( typeof callArgs[1].handleEvent === 'function' ) {
                    h = String(safe.Function_toString(callArgs[1].handleEvent));
                }
            } else {
                h = String(callArgs[1]);
            }
        } catch {
        }
        if ( type === '' && pattern === '' ) {
            safe.uboLog(logPrefix, `Called: ${t}\n${h}\n${elementDetails(thisArg)}`);
        } else if ( shouldPrevent(thisArg, t, h) ) {
            return safe.uboLog(logPrefix, `Prevented: ${t}\n${h}\n${elementDetails(thisArg)}`);
        }
        return context.reflect();
    };
    runAt(( ) => {
        proxyApplyFn('EventTarget.prototype.addEventListener', proxyFn);
        proxyApplyFn('document.addEventListener', proxyFn);
    }, extraArgs.runAt);
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'adjust-setInterval.js',
    aliases: [
        'nano-setInterval-booster.js',
        'nano-sib.js',
    ],
    fn: adjustSetInterval,
    dependencies: [
        'safe-self.fn',
    ],
});
// Imported from:
// https://github.com/NanoAdblocker/NanoFilters/blob/1f3be7211bb0809c5106996f52564bf10c4525f7/NanoFiltersSource/NanoResources.txt#L126
//
// Speed up or down setInterval, 3 optional arguments.
//      The payload matcher, a string literal or a JavaScript RegExp, defaults
//      to match all.
// delayMatcher
//      The delay matcher, an integer, defaults to 1000.
//      Use `*` to match any delay.
// boostRatio - The delay multiplier when there is a match, 0.5 speeds up by
//      2 times and 2 slows down by 2 times, defaults to 0.05 or speed up
//      20 times. Speed up and down both cap at 50 times.
function adjustSetInterval(
    needleArg = '',
    delayArg = '',
    boostArg = ''
) {
    if ( typeof needleArg !== 'string' ) { return; }
    const safe = safeSelf();
    const reNeedle = safe.patternToRegex(needleArg);
    let delay = delayArg !== '*' ? parseInt(delayArg, 10) : -1;
    if ( isNaN(delay) || isFinite(delay) === false ) { delay = 1000; }
    let boost = parseFloat(boostArg);
    boost = isNaN(boost) === false && isFinite(boost)
        ? Math.min(Math.max(boost, 0.001), 50)
        : 0.05;
    self.setInterval = new Proxy(self.setInterval, {
        apply: function(target, thisArg, args) {
            const [ a, b ] = args;
            if (
                (delay === -1 || b === delay) &&
                reNeedle.test(a.toString())
            ) {
                args[1] = b * boost;
            }
            return target.apply(thisArg, args);
        }
    });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'adjust-setTimeout.js',
    aliases: [
        'nano-setTimeout-booster.js',
        'nano-stb.js',
    ],
    fn: adjustSetTimeout,
    dependencies: [
        'safe-self.fn',
    ],
});
// Imported from:
// https://github.com/NanoAdblocker/NanoFilters/blob/1f3be7211bb0809c5106996f52564bf10c4525f7/NanoFiltersSource/NanoResources.txt#L82
//
// Speed up or down setTimeout, 3 optional arguments.
// funcMatcher
//      The payload matcher, a string literal or a JavaScript RegExp, defaults
//      to match all.
// delayMatcher
//      The delay matcher, an integer, defaults to 1000.
//      Use `*` to match any delay.
// boostRatio - The delay multiplier when there is a match, 0.5 speeds up by
//      2 times and 2 slows down by 2 times, defaults to 0.05 or speed up
//      20 times. Speed up and down both cap at 50 times.
function adjustSetTimeout(
    needleArg = '',
    delayArg = '',
    boostArg = ''
) {
    if ( typeof needleArg !== 'string' ) { return; }
    const safe = safeSelf();
    const reNeedle = safe.patternToRegex(needleArg);
    let delay = delayArg !== '*' ? parseInt(delayArg, 10) : -1;
    if ( isNaN(delay) || isFinite(delay) === false ) { delay = 1000; }
    let boost = parseFloat(boostArg);
    boost = isNaN(boost) === false && isFinite(boost)
        ? Math.min(Math.max(boost, 0.001), 50)
        : 0.05;
    self.setTimeout = new Proxy(self.setTimeout, {
        apply: function(target, thisArg, args) {
            const [ a, b ] = args;
            if (
                (delay === -1 || b === delay) &&
                reNeedle.test(a.toString())
            ) {
                args[1] = b * boost;
            }
            return target.apply(thisArg, args);
        }
    });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'prevent-fetch.js',
    aliases: [
        'no-fetch-if.js',
    ],
    fn: noFetchIf,
    dependencies: [
        'generate-content.fn',
        'proxy-apply.fn',
        'safe-self.fn',
    ],
});
function noFetchIf(
    propsToMatch = '',
    responseBody = '',
    responseType = ''
) {
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('prevent-fetch', propsToMatch, responseBody, responseType);
    const needles = [];
    for ( const condition of safe.String_split.call(propsToMatch, /\s+/) ) {
        if ( condition === '' ) { continue; }
        const pos = condition.indexOf(':');
        let key, value;
        if ( pos !== -1 ) {
            key = condition.slice(0, pos);
            value = condition.slice(pos + 1);
        } else {
            key = 'url';
            value = condition;
        }
        needles.push({ key, pattern: safe.initPattern(value, { canNegate: true }) });
    }
    const validResponseProps = {
        ok: [ false, true ],
        statusText: [ '', 'Not Found' ],
        type: [ 'basic', 'cors', 'default', 'error', 'opaque' ],
    };
    const responseProps = {
        statusText: { value: 'OK' },
    };
    if ( /^\{.*\}$/.test(responseType) ) {
        try {
            Object.entries(JSON.parse(responseType)).forEach(([ p, v ]) => {
                if ( validResponseProps[p] === undefined ) { return; }
                if ( validResponseProps[p].includes(v) === false ) { return; }
                responseProps[p] = { value: v };
            });
        }
        catch { }
    } else if ( responseType !== '' ) {
        if ( validResponseProps.type.includes(responseType) ) {
            responseProps.type = { value: responseType };
        }
    }
    proxyApplyFn('fetch', function fetch(context) {
        const { callArgs } = context;
        const details = callArgs[0] instanceof self.Request
            ? callArgs[0]
            : Object.assign({ url: callArgs[0] }, callArgs[1]);
        let proceed = true;
        try {
            const props = new Map();
            for ( const prop in details ) {
                let v = details[prop];
                if ( typeof v !== 'string' ) {
                    try { v = safe.JSON_stringify(v); }
                    catch { }
                }
                if ( typeof v !== 'string' ) { continue; }
                props.set(prop, v);
            }
            if ( safe.logLevel > 1 || propsToMatch === '' && responseBody === '' ) {
                const out = Array.from(props).map(a => `${a[0]}:${a[1]}`);
                safe.uboLog(logPrefix, `Called: ${out.join('\n')}`);
            }
            if ( propsToMatch === '' && responseBody === '' ) {
                return context.reflect();
            }
            proceed = needles.length === 0;
            for ( const { key, pattern } of needles ) {
                if (
                    pattern.expect && props.has(key) === false ||
                    safe.testPattern(pattern, props.get(key)) === false
                ) {
                    proceed = true;
                    break;
                }
            }
        } catch {
        }
        if ( proceed ) {
            return context.reflect();
        }
        return Promise.resolve(generateContentFn(false, responseBody)).then(text => {
            safe.uboLog(logPrefix, `Prevented with response "${text}"`);
            const response = new Response(text, {
                headers: {
                    'Content-Length': text.length,
                }
            });
            const props = Object.assign(
                { url: { value: details.url } },
                responseProps
            );
            safe.Object_defineProperties(response, props);
            return response;
        });
    });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'prevent-refresh.js',
    aliases: [
        'refresh-defuser.js',
    ],
    fn: preventRefresh,
    world: 'ISOLATED',
    dependencies: [
        'safe-self.fn',
    ],
});
// https://www.reddit.com/r/uBlockOrigin/comments/q0frv0/while_reading_a_sports_article_i_was_redirected/hf7wo9v/
function preventRefresh(
    delay = ''
) {
    if ( typeof delay !== 'string' ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('prevent-refresh', delay);
    const stop = content => {
        window.stop();
        safe.uboLog(logPrefix, `Prevented "${content}"`);
    };
    const defuse = ( ) => {
        const meta = document.querySelector('meta[http-equiv="refresh" i][content]');
        if ( meta === null ) { return; }
        const content = meta.getAttribute('content') || '';
        const ms = delay === ''
            ? Math.max(parseFloat(content) || 0, 0) * 500
            : 0;
        if ( ms === 0 ) {
            stop(content);
        } else {
            setTimeout(( ) => { stop(content); }, ms);
        }
    };
    self.addEventListener('load', defuse, { capture: true, once: true });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'remove-class.js',
    aliases: [
        'rc.js',
    ],
    fn: removeClass,
    world: 'ISOLATED',
    dependencies: [
        'run-at.fn',
        'safe-self.fn',
    ],
});
function removeClass(
    rawToken = '',
    rawSelector = '',
    behavior = ''
) {
    if ( typeof rawToken !== 'string' ) { return; }
    if ( rawToken === '' ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('remove-class', rawToken, rawSelector, behavior);
    const tokens = safe.String_split.call(rawToken, /\s*\|\s*/);
    const selector = tokens
        .map(a => `${rawSelector}.${CSS.escape(a)}`)
        .join(',');
    if ( safe.logLevel > 1 ) {
        safe.uboLog(logPrefix, `Target selector:\n\t${selector}`);
    }
    const mustStay = /\bstay\b/.test(behavior);
    let timer;
    const rmclass = ( ) => {
        timer = undefined;
        try {
            const nodes = document.querySelectorAll(selector);
            for ( const node of nodes ) {
                node.classList.remove(...tokens);
                safe.uboLog(logPrefix, 'Removed class(es)');
            }
        } catch {
        }
        if ( mustStay ) { return; }
        if ( document.readyState !== 'complete' ) { return; }
        observer.disconnect();
    };
    const mutationHandler = mutations => {
        if ( timer !== undefined ) { return; }
        let skip = true;
        for ( let i = 0; i < mutations.length && skip; i++ ) {
            const { type, addedNodes, removedNodes } = mutations[i];
            if ( type === 'attributes' ) { skip = false; }
            for ( let j = 0; j < addedNodes.length && skip; j++ ) {
                if ( addedNodes[j].nodeType === 1 ) { skip = false; break; }
            }
            for ( let j = 0; j < removedNodes.length && skip; j++ ) {
                if ( removedNodes[j].nodeType === 1 ) { skip = false; break; }
            }
        }
        if ( skip ) { return; }
        timer = safe.onIdle(rmclass, { timeout: 67 });
    };
    const observer = new MutationObserver(mutationHandler);
    const start = ( ) => {
        rmclass();
        observer.observe(document, {
            attributes: true,
            attributeFilter: [ 'class' ],
            childList: true,
            subtree: true,
        });
    };
    runAt(( ) => {
        start();
    }, /\bcomplete\b/.test(behavior) ? 'idle' : 'loading');
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'webrtc-if.js',
    fn: webrtcIf,
    dependencies: [
        'safe-self.fn',
    ],
});
function webrtcIf(
    good = ''
) {
    if ( typeof good !== 'string' ) { return; }
    const safe = safeSelf();
    const reGood = safe.patternToRegex(good);
    const rtcName = window.RTCPeerConnection
        ? 'RTCPeerConnection'
        : (window.webkitRTCPeerConnection ? 'webkitRTCPeerConnection' : '');
    if ( rtcName === '' ) { return; }
    const log = console.log.bind(console);
    const neuteredPeerConnections = new WeakSet();
    const isGoodConfig = function(instance, config) {
        if ( neuteredPeerConnections.has(instance) ) { return false; }
        if ( config instanceof Object === false ) { return true; }
        if ( Array.isArray(config.iceServers) === false ) { return true; }
        for ( const server of config.iceServers ) {
            const urls = typeof server.urls === 'string'
                ? [ server.urls ]
                : server.urls;
            if ( Array.isArray(urls) ) {
                for ( const url of urls ) {
                    if ( reGood.test(url) ) { return true; }
                }
            }
            if ( typeof server.username === 'string' ) {
                if ( reGood.test(server.username) ) { return true; }
            }
            if ( typeof server.credential === 'string' ) {
                if ( reGood.test(server.credential) ) { return true; }
            }
        }
        neuteredPeerConnections.add(instance);
        return false;
    };
    const peerConnectionCtor = window[rtcName];
    const peerConnectionProto = peerConnectionCtor.prototype;
    peerConnectionProto.createDataChannel =
        new Proxy(peerConnectionProto.createDataChannel, {
            apply: function(target, thisArg, args) {
                if ( isGoodConfig(target, args[1]) === false ) {
                    log('uBO:', args[1]);
                    return Reflect.apply(target, thisArg, args.slice(0, 1));
                }
                return Reflect.apply(target, thisArg, args);
            },
        });
    window[rtcName] =
        new Proxy(peerConnectionCtor, {
            construct: function(target, args) {
                if ( isGoodConfig(target, args[0]) === false ) {
                    log('uBO:', args[0]);
                    return Reflect.construct(target);
                }
                return Reflect.construct(target, args);
            }
        });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'prevent-xhr.js',
    aliases: [
        'no-xhr-if.js',
    ],
    fn: preventXhr,
    dependencies: [
        'prevent-xhr.fn',
    ],
});
function preventXhr(...args) {
    return preventXhrFn(false, ...args);
}

/**
 * @scriptlet prevent-window-open
 * 
 * @description
 * Prevent a webpage from opening new tabs through `window.open()`.
 * 
 * @param pattern
 * A plain string or regex to match against the `url` argument for the
 * prevention to be triggered. If not provided, all calls to `window.open()`
 * are prevented.
 * If set to the special value `debug` *and* the logger is opened, the scriptlet
 * will trigger a `debugger` statement and the prevention will not occur.
 * 
 * @param [delay]
 * If provided, a decoy will be created or opened, and this parameter states
 * the number of seconds to wait for before the decoy is terminated, i.e.
 * either removed from the DOM or closed.
 * 
 * @param [decoy]
 * A string representing the type of decoy to use:
 * - `blank`: replace the `url` parameter with `about:blank`
 * - `object`: create and append an `object` element to the DOM, and return
 *   its `contentWindow` property.
 * - `frame`: create and append an `iframe` element to the DOM, and return
 *   its `contentWindow` property.
 * 
 * @example
 * ##+js(prevent-window-open, ads.example.com/)
 * 
 * @example
 * ##+js(prevent-window-open, ads.example.com/, 1, iframe)
 * 
 * */

builtinScriptlets.push({
    name: 'prevent-window-open.js',
    aliases: [
        'nowoif.js',
        'no-window-open-if.js',
        'window.open-defuser.js',
    ],
    fn: noWindowOpenIf,
    dependencies: [
        'proxy-apply.fn',
        'safe-self.fn',
    ],
});
function noWindowOpenIf(
    pattern = '',
    delay = '',
    decoy = ''
) {
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('no-window-open-if', pattern, delay, decoy);
    const targetMatchResult = pattern.startsWith('!') === false;
    if ( targetMatchResult === false ) {
        pattern = pattern.slice(1);
    }
    const rePattern = safe.patternToRegex(pattern);
    const autoRemoveAfter = (parseFloat(delay) || 0) * 1000;
    const setTimeout = self.setTimeout;
    const createDecoy = function(tag, urlProp, url) {
        const decoyElem = document.createElement(tag);
        decoyElem[urlProp] = url;
        decoyElem.style.setProperty('height','1px', 'important');
        decoyElem.style.setProperty('position','fixed', 'important');
        decoyElem.style.setProperty('top','-1px', 'important');
        decoyElem.style.setProperty('width','1px', 'important');
        document.body.appendChild(decoyElem);
        setTimeout(( ) => { decoyElem.remove(); }, autoRemoveAfter);
        return decoyElem;
    };
    const noopFunc = function(){};
    proxyApplyFn('open', function open(context) {
        if ( pattern === 'debug' && safe.logLevel !== 0 ) {
            debugger; // eslint-disable-line no-debugger
            return context.reflect();
        }
        const { callArgs } = context;
        const haystack = callArgs.join(' ');
        if ( rePattern.test(haystack) !== targetMatchResult ) {
            if ( safe.logLevel > 1 ) {
                safe.uboLog(logPrefix, `Allowed (${callArgs.join(', ')})`);
            }
            return context.reflect();
        }
        safe.uboLog(logPrefix, `Prevented (${callArgs.join(', ')})`);
        if ( delay === '' ) { return null; }
        if ( decoy === 'blank' ) {
            callArgs[0] = 'about:blank';
            const r = context.reflect();
            setTimeout(( ) => { r.close(); }, autoRemoveAfter);
            return r;
        }
        const decoyElem = decoy === 'obj'
            ? createDecoy('object', 'data', ...callArgs)
            : createDecoy('iframe', 'src', ...callArgs);
        let popup = decoyElem.contentWindow;
        if ( typeof popup === 'object' && popup !== null ) {
            Object.defineProperty(popup, 'closed', { value: false });
        } else {
            popup = new Proxy(self, {
                get: function(target, prop, ...args) {
                    if ( prop === 'closed' ) { return false; }
                    const r = Reflect.get(target, prop, ...args);
                    if ( typeof r === 'function' ) { return noopFunc; }
                    return r;
                },
                set: function(...args) {
                    return Reflect.set(...args);
                },
            });
        }
        if ( safe.logLevel !== 0 ) {
            popup = new Proxy(popup, {
                get: function(target, prop, ...args) {
                    const r = Reflect.get(target, prop, ...args);
                    safe.uboLog(logPrefix, `popup / get ${prop} === ${r}`);
                    if ( typeof r === 'function' ) {
                        return (...args) => { return r.call(target, ...args); };
                    }
                    return r;
                },
                set: function(target, prop, value, ...args) {
                    safe.uboLog(logPrefix, `popup / set ${prop} = ${value}`);
                    return Reflect.set(target, prop, value, ...args);
                },
            });
        }
        return popup;
    });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'close-window.js',
    aliases: [
        'window-close-if.js',
    ],
    fn: closeWindow,
    world: 'ISOLATED',
    dependencies: [
        'safe-self.fn',
    ],
});
// https://github.com/uBlockOrigin/uAssets/issues/10323#issuecomment-992312847
// https://github.com/AdguardTeam/Scriptlets/issues/158
// https://github.com/uBlockOrigin/uBlock-issues/discussions/2270
function closeWindow(
    arg1 = ''
) {
    if ( typeof arg1 !== 'string' ) { return; }
    const safe = safeSelf();
    let subject = '';
    if ( /^\/.*\/$/.test(arg1) ) {
        subject = window.location.href;
    } else if ( arg1 !== '' ) {
        subject = `${window.location.pathname}${window.location.search}`;
    }
    try {
        const re = safe.patternToRegex(arg1);
        if ( re.test(subject) ) {
            window.close();
        }
    } catch(ex) {
        console.log(ex);
    }
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'window.name-defuser.js',
    fn: windowNameDefuser,
});
// https://github.com/gorhill/uBlock/issues/1228
function windowNameDefuser() {
    if ( window === window.top ) {
        window.name = '';
    }
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'overlay-buster.js',
    fn: overlayBuster,
});
// Experimental: Generic nuisance overlay buster.
// if this works well and proves to be useful, this may end up
// as a stock tool in uBO's popup panel.
function overlayBuster(allFrames) {
    if ( allFrames === '' && window !== window.top ) { return; }
    var tstart;
    var ttl = 30000;
    var delay = 0;
    var delayStep = 50;
    var buster = function() {
        var docEl = document.documentElement,
            bodyEl = document.body,
            vw = Math.min(docEl.clientWidth, window.innerWidth),
            vh = Math.min(docEl.clientHeight, window.innerHeight),
            tol = Math.min(vw, vh) * 0.05,
            el = document.elementFromPoint(vw/2, vh/2),
            style, rect;
        for (;;) {
            if ( el === null || el.parentNode === null || el === bodyEl ) {
                break;
            }
            style = window.getComputedStyle(el);
            if ( parseInt(style.zIndex, 10) >= 1000 || style.position === 'fixed' ) {
                rect = el.getBoundingClientRect();
                if ( rect.left <= tol && rect.top <= tol && (vw - rect.right) <= tol && (vh - rect.bottom) < tol ) {
                    el.parentNode.removeChild(el);
                    tstart = Date.now();
                    el = document.elementFromPoint(vw/2, vh/2);
                    bodyEl.style.setProperty('overflow', 'auto', 'important');
                    docEl.style.setProperty('overflow', 'auto', 'important');
                    continue;
                }
            }
            el = el.parentNode;
        }
        if ( (Date.now() - tstart) < ttl ) {
            delay = Math.min(delay + delayStep, 1000);
            setTimeout(buster, delay);
        }
    };
    var domReady = function(ev) {
        if ( ev ) {
            document.removeEventListener(ev.type, domReady);
        }
        tstart = Date.now();
        setTimeout(buster, delay);
    };
    if ( document.readyState === 'loading' ) {
        document.addEventListener('DOMContentLoaded', domReady);
    } else {
        domReady();
    }
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'alert-buster.js',
    fn: alertBuster,
});
// https://github.com/uBlockOrigin/uAssets/issues/8
function alertBuster() {
    window.alert = new Proxy(window.alert, {
        apply: function(a) {
            console.info(a);
        },
        get(target, prop) {
            if ( prop === 'toString' ) {
                return target.toString.bind(target);
            }
            return Reflect.get(target, prop);
        },
    });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'nowebrtc.js',
    fn: noWebrtc,
});
// Prevent web pages from using RTCPeerConnection(), and report attempts in console.
function noWebrtc() {
    var rtcName = window.RTCPeerConnection ? 'RTCPeerConnection' : (
        window.webkitRTCPeerConnection ? 'webkitRTCPeerConnection' : ''
    );
    if ( rtcName === '' ) { return; }
    var log = console.log.bind(console);
    var pc = function(cfg) {
        log('Document tried to create an RTCPeerConnection: %o', cfg);
    };
    const noop = function() {
    };
    pc.prototype = {
        close: noop,
        createDataChannel: noop,
        createOffer: noop,
        setRemoteDescription: noop,
        toString: function() {
            return '[object RTCPeerConnection]';
        }
    };
    var z = window[rtcName];
    window[rtcName] = pc.bind(window);
    if ( z.prototype ) {
        z.prototype.createDataChannel = function() {
            return {
                close: function() {},
                send: function() {}
            };
        }.bind(null);
    }
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'disable-newtab-links.js',
    fn: disableNewtabLinks,
});
// https://github.com/uBlockOrigin/uAssets/issues/913
function disableNewtabLinks() {
    document.addEventListener('click', ev => {
        let target = ev.target;
        while ( target !== null ) {
            if ( target.localName === 'a' && target.hasAttribute('target') ) {
                ev.stopPropagation();
                ev.preventDefault();
                break;
            }
            target = target.parentNode;
        }
    }, { capture: true });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'xml-prune.js',
    fn: xmlPrune,
    dependencies: [
        'safe-self.fn',
    ],
});
function xmlPrune(
    selector = '',
    selectorCheck = '',
    urlPattern = ''
) {
    if ( typeof selector !== 'string' ) { return; }
    if ( selector === '' ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('xml-prune', selector, selectorCheck, urlPattern);
    const reUrl = safe.patternToRegex(urlPattern);
    const extraArgs = safe.getExtraArgs(Array.from(arguments), 3);
    const queryAll = (xmlDoc, selector) => {
        const isXpath = /^xpath\(.+\)$/.test(selector);
        if ( isXpath === false ) {
            return Array.from(xmlDoc.querySelectorAll(selector));
        }
        const xpr = xmlDoc.evaluate(
            selector.slice(6, -1),
            xmlDoc,
            null,
            XPathResult.UNORDERED_NODE_SNAPSHOT_TYPE,
            null
        );
        const out = [];
        for ( let i = 0; i < xpr.snapshotLength; i++ ) {
            const node = xpr.snapshotItem(i);
            out.push(node);
        }
        return out;
    };
    const pruneFromDoc = xmlDoc => {
        try {
            if ( selectorCheck !== '' && xmlDoc.querySelector(selectorCheck) === null ) {
                return xmlDoc;
            }
            if ( extraArgs.logdoc ) {
                const serializer = new XMLSerializer();
                safe.uboLog(logPrefix, `Document is\n\t${serializer.serializeToString(xmlDoc)}`);
            }
            const items = queryAll(xmlDoc, selector);
            if ( items.length === 0 ) { return xmlDoc; }
            safe.uboLog(logPrefix, `Removing ${items.length} items`);
            for ( const item of items ) {
                if ( item.nodeType === 1 ) {
                    item.remove();
                } else if ( item.nodeType === 2 ) {
                    item.ownerElement.removeAttribute(item.nodeName);
                }
                safe.uboLog(logPrefix, `${item.constructor.name}.${item.nodeName} removed`);
            }
        } catch(ex) {
            safe.uboErr(logPrefix, `Error: ${ex}`);
        }
        return xmlDoc;
    };
    const pruneFromText = text => {
        if ( (/^\s*</.test(text) && />\s*$/.test(text)) === false ) {
            return text;
        }
        try {
            const xmlParser = new DOMParser();
            const xmlDoc = xmlParser.parseFromString(text, 'text/xml');
            pruneFromDoc(xmlDoc);
            const serializer = new XMLSerializer();
            text = serializer.serializeToString(xmlDoc);
        } catch {
        }
        return text;
    };
    const urlFromArg = arg => {
        if ( typeof arg === 'string' ) { return arg; }
        if ( arg instanceof Request ) { return arg.url; }
        return String(arg);
    };
    self.fetch = new Proxy(self.fetch, {
        apply: function(target, thisArg, args) {
            const fetchPromise = Reflect.apply(target, thisArg, args);
            if ( reUrl.test(urlFromArg(args[0])) === false ) {
                return fetchPromise;
            }
            return fetchPromise.then(responseBefore => {
                const response = responseBefore.clone();
                return response.text().then(text => {
                    const responseAfter = new Response(pruneFromText(text), {
                        status: responseBefore.status,
                        statusText: responseBefore.statusText,
                        headers: responseBefore.headers,
                    });
                    Object.defineProperties(responseAfter, {
                        ok: { value: responseBefore.ok },
                        redirected: { value: responseBefore.redirected },
                        type: { value: responseBefore.type },
                        url: { value: responseBefore.url },
                    });
                    return responseAfter;
                }).catch(( ) =>
                    responseBefore
                );
            });
        }
    });
    self.XMLHttpRequest.prototype.open = new Proxy(self.XMLHttpRequest.prototype.open, {
        apply: async (target, thisArg, args) => {
            if ( reUrl.test(urlFromArg(args[1])) === false ) {
                return Reflect.apply(target, thisArg, args);
            }
            thisArg.addEventListener('readystatechange', function() {
                if ( thisArg.readyState !== 4 ) { return; }
                const type = thisArg.responseType;
                if (
                    type === 'document' ||
                    type === '' && thisArg.responseXML instanceof XMLDocument
                ) {
                    pruneFromDoc(thisArg.responseXML);
                    const serializer = new XMLSerializer();
                    const textout = serializer.serializeToString(thisArg.responseXML);
                    Object.defineProperty(thisArg, 'responseText', { value: textout });
                    if ( typeof thisArg.response === 'string' ) {
                        Object.defineProperty(thisArg, 'response', { value: textout });
                    }
                    return;
                }
                if (
                    type === 'text' ||
                    type === '' && typeof thisArg.responseText === 'string'
                ) {
                    const textin = thisArg.responseText;
                    const textout = pruneFromText(textin);
                    if ( textout === textin ) { return; }
                    Object.defineProperty(thisArg, 'response', { value: textout });
                    Object.defineProperty(thisArg, 'responseText', { value: textout });
                    return;
                }
            });
            return Reflect.apply(target, thisArg, args);
        }
    });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'm3u-prune.js',
    fn: m3uPrune,
    dependencies: [
        'safe-self.fn',
    ],
});
// https://en.wikipedia.org/wiki/M3U
function m3uPrune(
    m3uPattern = '',
    urlPattern = ''
) {
    if ( typeof m3uPattern !== 'string' ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('m3u-prune', m3uPattern, urlPattern);
    const toLog = [];
    const regexFromArg = arg => {
        if ( arg === '' ) { return /^/; }
        const match = /^\/(.+)\/([gms]*)$/.exec(arg);
        if ( match !== null ) {
            let flags = match[2] || '';
            if ( flags.includes('m') ) { flags += 's'; }
            return new RegExp(match[1], flags);
        }
        return new RegExp(
            arg.replace(/[.+?^${}()|[\]\\]/g, '\\$&').replace(/\*+/g, '.*?')
        );
    };
    const reM3u = regexFromArg(m3uPattern);
    const reUrl = regexFromArg(urlPattern);
    const pruneSpliceoutBlock = (lines, i) => {
        if ( lines[i].startsWith('#EXT-X-CUE:TYPE="SpliceOut"') === false ) {
            return false;
        }
        toLog.push(`\t${lines[i]}`);
        lines[i] = undefined; i += 1;
        if ( lines[i].startsWith('#EXT-X-ASSET:CAID') ) {
            toLog.push(`\t${lines[i]}`);
            lines[i] = undefined; i += 1;
        }
        if ( lines[i].startsWith('#EXT-X-SCTE35:') ) {
            toLog.push(`\t${lines[i]}`);
            lines[i] = undefined; i += 1;
        }
        if ( lines[i].startsWith('#EXT-X-CUE-IN') ) {
            toLog.push(`\t${lines[i]}`);
            lines[i] = undefined; i += 1;
        }
        if ( lines[i].startsWith('#EXT-X-SCTE35:') ) {
            toLog.push(`\t${lines[i]}`);
            lines[i] = undefined; i += 1;
        }
        return true;
    };
    const pruneInfBlock = (lines, i) => {
        if ( lines[i].startsWith('#EXTINF') === false ) { return false; }
        if ( reM3u.test(lines[i+1]) === false ) { return false; }
        toLog.push('Discarding', `\t${lines[i]}, \t${lines[i+1]}`);
        lines[i] = lines[i+1] = undefined; i += 2;
        if ( lines[i].startsWith('#EXT-X-DISCONTINUITY') ) {
            toLog.push(`\t${lines[i]}`);
            lines[i] = undefined; i += 1;
        }
        return true;
    };
    const pruner = text => {
        if ( (/^\s*#EXTM3U/.test(text)) === false ) { return text; }
        if ( m3uPattern === '' ) {
            safe.uboLog(` Content:\n${text}`);
            return text;
        }
        if ( reM3u.multiline ) {
            reM3u.lastIndex = 0;
            for (;;) {
                const match = reM3u.exec(text);
                if ( match === null ) { break; }
                let discard = match[0];
                let before = text.slice(0, match.index);
                if (
                    /^[\n\r]+/.test(discard) === false &&
                    /[\n\r]+$/.test(before) === false
                ) {
                    const startOfLine = /[^\n\r]+$/.exec(before);
                    if ( startOfLine !== null ) {
                        before = before.slice(0, startOfLine.index);
                        discard = startOfLine[0] + discard;
                    }
                }
                let after = text.slice(match.index + match[0].length);
                if (
                    /[\n\r]+$/.test(discard) === false &&
                    /^[\n\r]+/.test(after) === false
                ) {
                    const endOfLine = /^[^\n\r]+/.exec(after);
                    if ( endOfLine !== null ) {
                        after = after.slice(endOfLine.index);
                        discard += discard + endOfLine[0];
                    }
                }
                text = before.trim() + '\n' + after.trim();
                reM3u.lastIndex = before.length + 1;
                toLog.push('Discarding', ...safe.String_split.call(discard, /\n+/).map(s => `\t${s}`));
                if ( reM3u.global === false ) { break; }
            }
            return text;
        }
        const lines = safe.String_split.call(text, /\n\r|\n|\r/);
        for ( let i = 0; i < lines.length; i++ ) {
            if ( lines[i] === undefined ) { continue; }
            if ( pruneSpliceoutBlock(lines, i) ) { continue; }
            if ( pruneInfBlock(lines, i) ) { continue; }
        }
        return lines.filter(l => l !== undefined).join('\n');
    };
    const urlFromArg = arg => {
        if ( typeof arg === 'string' ) { return arg; }
        if ( arg instanceof Request ) { return arg.url; }
        return String(arg);
    };
    const realFetch = self.fetch;
    self.fetch = new Proxy(self.fetch, {
        apply: function(target, thisArg, args) {
            if ( reUrl.test(urlFromArg(args[0])) === false ) {
                return Reflect.apply(target, thisArg, args);
            }
            return realFetch(...args).then(realResponse =>
                realResponse.text().then(text => {
                    const response = new Response(pruner(text), {
                        status: realResponse.status,
                        statusText: realResponse.statusText,
                        headers: realResponse.headers,
                    });
                    if ( toLog.length !== 0 ) {
                        toLog.unshift(logPrefix);
                        safe.uboLog(toLog.join('\n'));
                    }
                    return response;
                })
            );
        }
    });
    self.XMLHttpRequest.prototype.open = new Proxy(self.XMLHttpRequest.prototype.open, {
        apply: async (target, thisArg, args) => {
            if ( reUrl.test(urlFromArg(args[1])) === false ) {
                return Reflect.apply(target, thisArg, args);
            }
            thisArg.addEventListener('readystatechange', function() {
                if ( thisArg.readyState !== 4 ) { return; }
                const type = thisArg.responseType;
                if ( type !== '' && type !== 'text' ) { return; }
                const textin = thisArg.responseText;
                const textout = pruner(textin);
                if ( textout === textin ) { return; }
                Object.defineProperty(thisArg, 'response', { value: textout });
                Object.defineProperty(thisArg, 'responseText', { value: textout });
                if ( toLog.length !== 0 ) {
                    toLog.unshift(logPrefix);
                    safe.uboLog(toLog.join('\n'));
                }
            });
            return Reflect.apply(target, thisArg, args);
        }
    });
}

/*******************************************************************************
 * 
 * @scriptlet call-nothrow
 * 
 * @description
 * Prevent a function call from throwing. The function will be called, however
 * should it throw, the scriptlet will silently process the exception and
 * returns as if no exception has occurred.
 * 
 * ### Syntax
 * 
 * ```text
 * example.org##+js(call-nothrow, propertyChain)
 * ```
 * 
 * - `propertyChain`: a chain of dot-separated properties which leads to the
 * function to be trapped.
 * 
 * ### Examples
 * 
 * example.org##+js(call-nothrow, Object.defineProperty)
 * 
 * */

builtinScriptlets.push({
    name: 'call-nothrow.js',
    fn: callNothrow,
    dependencies: [
        'safe-self.fn',
    ],
});
function callNothrow(
    chain = ''
) {
    if ( typeof chain !== 'string' ) { return; }
    if ( chain === '' ) { return; }
    const safe = safeSelf();
    const parts = safe.String_split.call(chain, '.');
    let owner = window, prop;
    for (;;) {
        prop = parts.shift();
        if ( parts.length === 0 ) { break; }
        owner = owner[prop];
        if ( owner instanceof Object === false ) { return; }
    }
    if ( prop === '' ) { return; }
    const fn = owner[prop];
    if ( typeof fn !== 'function' ) { return; }
    owner[prop] = new Proxy(fn, {
        apply: function(...args) {
            let r;
            try {
                r = Reflect.apply(...args);
            } catch {
            }
            return r;
        },
    });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'remove-node-text.js',
    aliases: [
        'rmnt.js',
    ],
    fn: removeNodeText,
    world: 'ISOLATED',
    dependencies: [
        'replace-node-text.fn',
    ],
});
function removeNodeText(
    nodeName,
    includes,
    ...extraArgs
) {
    replaceNodeTextFn(nodeName, '', '', 'includes', includes || '', ...extraArgs);
}

/*******************************************************************************
 * 
 * @scriptlet prevent-canvas
 * 
 * @description
 * Prevent usage of specific or all (default) canvas APIs.
 *
 * ### Syntax
 * 
 * ```text
 * example.com##+js(prevent-canvas [, contextType])
 * ```
 * 
 * - `contextType`: A specific type of canvas API to prevent (default to all
 *   APIs). Can be a string or regex which will be matched against the type
 *   used in getContext() call. Prepend with `!` to test for no-match.
 * 
 * ### Examples
 * 
 * 1. Prevent `example.com` from accessing all canvas APIs
 * 
 * ```adblock
 * example.com##+js(prevent-canvas)
 * ```
 * 
 * 2. Prevent access to any flavor of WebGL API, everywhere
 * 
 * ```adblock
 * *##+js(prevent-canvas, /webgl/)
 * ```
 * 
 * 3. Prevent `example.com` from accessing any flavor of canvas API except `2d`
 * 
 * ```adblock
 * example.com##+js(prevent-canvas, !2d)
 * ```
 * 
 * ### References
 * 
 * https://developer.mozilla.org/en-US/docs/Web/API/HTMLCanvasElement/getContext
 * 
 * */

builtinScriptlets.push({
    name: 'prevent-canvas.js',
    fn: preventCanvas,
    dependencies: [
        'safe-self.fn',
    ],
});
function preventCanvas(
    contextType = ''
) {
    const safe = safeSelf();
    const pattern = safe.initPattern(contextType, { canNegate: true });
    const proto = globalThis.HTMLCanvasElement.prototype;
    proto.getContext = new Proxy(proto.getContext, {
        apply(target, thisArg, args) {
            if ( safe.testPattern(pattern, args[0]) ) { return null; }
            return Reflect.apply(target, thisArg, args);
        }
    });
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'multiup.js',
    fn: multiup,
    world: 'ISOLATED',
});
function multiup() {
    const handler = ev => {
        const target = ev.target;
        if ( target.matches('button[link]') === false ) { return; }
        const ancestor = target.closest('form');
        if ( ancestor === null ) { return; }
        if ( ancestor !== target.parentElement ) { return; }
        const link = (target.getAttribute('link') || '').trim();
        if ( link === '' ) { return; }
        ev.preventDefault();
        ev.stopPropagation();
        document.location.href = link;
    };
    document.addEventListener('click', handler, { capture: true });
}



/*******************************************************************************
 * 
 * Scriplets below this section are only available for filter lists from
 * trusted sources. They all have the property `requiresTrust` set to `true`.
 * 
 * Trusted sources are:
 *
 * - uBO's own filter lists, which name starts with "uBlock filters – ", and
 *   maintained at: https://github.com/uBlockOrigin/uAssets
 * 
 * - The user's own filters as seen in "My filters" pane in uBO's dashboard. 
 * 
 * The trustworthiness of filters using these privileged scriptlets are
 * evaluated at filter list compiled time: when a filter using one of the
 * privileged scriptlet originates from a non-trusted filter list source, it
 * is discarded at compile time, specifically from within:
 * 
 * - Source: ./src/js/scriptlet-filtering.js
 * - Method: scriptletFilteringEngine.compile(), via normalizeRawFilter()
 * 
 **/

/*******************************************************************************
 * 
 * replace-node-text.js
 * 
 * Replace text instance(s) with another text instance inside specific
 * DOM nodes. By default, the scriplet stops and quits at the interactive
 * stage of a document.
 * 
 * See commit messages for usage:
 * - https://github.com/gorhill/uBlock/commit/99ce027fd702
 * - https://github.com/gorhill/uBlock/commit/41876336db48
 * 
 **/

builtinScriptlets.push({
    name: 'trusted-replace-node-text.js',
    requiresTrust: true,
    aliases: [
        'trusted-rpnt.js',
        'replace-node-text.js',
        'rpnt.js',
    ],
    fn: replaceNodeText,
    world: 'ISOLATED',
    dependencies: [
        'replace-node-text.fn',
    ],
});
function replaceNodeText(
    nodeName,
    pattern,
    replacement,
    ...extraArgs
) {
    replaceNodeTextFn(nodeName, pattern, replacement, ...extraArgs);
}

/*******************************************************************************
 * 
 * trusted-replace-fetch-response.js
 * 
 * Replaces response text content of fetch requests if all given parameters
 * match.
 * 
 * Reference:
 * https://github.com/AdguardTeam/Scriptlets/blob/master/src/scriptlets/trusted-replace-fetch-response.js
 * 
 **/

builtinScriptlets.push({
    name: 'trusted-replace-fetch-response.js',
    requiresTrust: true,
    aliases: [
        'trusted-rpfr.js',
    ],
    fn: trustedReplaceFetchResponse,
    dependencies: [
        'replace-fetch-response.fn',
    ],
});
function trustedReplaceFetchResponse(...args) {
    replaceFetchResponseFn(true, ...args);
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'trusted-replace-xhr-response.js',
    requiresTrust: true,
    fn: trustedReplaceXhrResponse,
    dependencies: [
        'match-object-properties.fn',
        'parse-properties-to-match.fn',
        'safe-self.fn',
    ],
});
function trustedReplaceXhrResponse(
    pattern = '',
    replacement = '',
    propsToMatch = ''
) {
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('trusted-replace-xhr-response', pattern, replacement, propsToMatch);
    const xhrInstances = new WeakMap();
    if ( pattern === '*' ) { pattern = '.*'; }
    const rePattern = safe.patternToRegex(pattern);
    const propNeedles = parsePropertiesToMatchFn(propsToMatch, 'url');
    const extraArgs = safe.getExtraArgs(Array.from(arguments), 3);
    const reIncludes = extraArgs.includes ? safe.patternToRegex(extraArgs.includes) : null;
    self.XMLHttpRequest = class extends self.XMLHttpRequest {
        open(method, url, ...args) {
            const outerXhr = this;
            const xhrDetails = { method, url };
            let outcome = 'match';
            if ( propNeedles.size !== 0 ) {
                if ( matchObjectPropertiesFn(propNeedles, xhrDetails) === undefined ) {
                    outcome = 'nomatch';
                }
            }
            if ( outcome === 'match' ) {
                if ( safe.logLevel > 1 ) {
                    safe.uboLog(logPrefix, `Matched "propsToMatch"`);
                }
                xhrInstances.set(outerXhr, xhrDetails);
            }
            return super.open(method, url, ...args);
        }
        get response() {
            const innerResponse = super.response;
            const xhrDetails = xhrInstances.get(this);
            if ( xhrDetails === undefined ) {
                return innerResponse;
            }
            const responseLength = typeof innerResponse === 'string'
                ? innerResponse.length
                : undefined;
            if ( xhrDetails.lastResponseLength !== responseLength ) {
                xhrDetails.response = undefined;
                xhrDetails.lastResponseLength = responseLength;
            }
            if ( xhrDetails.response !== undefined ) {
                return xhrDetails.response;
            }
            if ( typeof innerResponse !== 'string' ) {
                return (xhrDetails.response = innerResponse);
            }
            if ( reIncludes && reIncludes.test(innerResponse) === false ) {
                return (xhrDetails.response = innerResponse);
            }
            const textBefore = innerResponse;
            const textAfter = textBefore.replace(rePattern, replacement);
            if ( textAfter !== textBefore ) {
                safe.uboLog(logPrefix, 'Match');
            }
            return (xhrDetails.response = textAfter);
        }
        get responseText() {
            const response = this.response;
            if ( typeof response !== 'string' ) {
                return super.responseText;
            }
            return response;
        }
    };
}

/*******************************************************************************
 * 
 * trusted-click-element.js
 * 
 * Reference API:
 * https://github.com/AdguardTeam/Scriptlets/blob/master/src/scriptlets/trusted-click-element.js
 * 
 **/

builtinScriptlets.push({
    name: 'trusted-click-element.js',
    requiresTrust: true,
    fn: trustedClickElement,
    world: 'ISOLATED',
    dependencies: [
        'get-all-cookies.fn',
        'get-all-local-storage.fn',
        'run-at-html-element.fn',
        'safe-self.fn',
    ],
});
function trustedClickElement(
    selectors = '',
    extraMatch = '',
    delay = ''
) {
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('trusted-click-element', selectors, extraMatch, delay);

    if ( extraMatch !== '' ) {
        const assertions = safe.String_split.call(extraMatch, ',').map(s => {
            const pos1 = s.indexOf(':');
            const s1 = pos1 !== -1 ? s.slice(0, pos1) : s;
            const not = s1.startsWith('!');
            const type = not ? s1.slice(1) : s1;
            const s2 = pos1 !== -1 ? s.slice(pos1+1).trim() : '';
            if ( s2 === '' ) { return; }
            const out = { not, type };
            const match = /^\/(.+)\/(i?)$/.exec(s2);
            if ( match !== null ) {
                out.re = new RegExp(match[1], match[2] || undefined);
                return out;
            }
            const pos2 = s2.indexOf('=');
            const key = pos2 !== -1 ? s2.slice(0, pos2).trim() : s2;
            const value = pos2 !== -1 ? s2.slice(pos2+1).trim() : '';
            out.re = new RegExp(`^${this.escapeRegexChars(key)}=${this.escapeRegexChars(value)}`);
            return out;
        }).filter(details => details !== undefined);
        const allCookies = assertions.some(o => o.type === 'cookie')
            ? getAllCookiesFn()
            : [];
        const allStorageItems = assertions.some(o => o.type === 'localStorage')
            ? getAllLocalStorageFn()
            : [];
        const hasNeedle = (haystack, needle) => {
            for ( const { key, value } of haystack ) {
                if ( needle.test(`${key}=${value}`) ) { return true; }
            }
            return false;
        };
        for ( const { not, type, re } of assertions ) {
            switch ( type ) {
            case 'cookie':
                if ( hasNeedle(allCookies, re) === not ) { return; }
                break;
            case 'localStorage':
                if ( hasNeedle(allStorageItems, re) === not ) { return; }
                break;
            }
        }
    }

    const getShadowRoot = elem => {
        // Firefox
        if ( elem.openOrClosedShadowRoot ) {
            return elem.openOrClosedShadowRoot;
        }
        // Chromium
        if ( typeof chrome === 'object' ) {
            if ( chrome.dom && chrome.dom.openOrClosedShadowRoot ) {
                return chrome.dom.openOrClosedShadowRoot(elem);
            }
        }
        return null;
    };

    const querySelectorEx = (selector, context = document) => {
        const pos = selector.indexOf(' >>> ');
        if ( pos === -1 ) { return context.querySelector(selector); }
        const outside = selector.slice(0, pos).trim();
        const inside = selector.slice(pos + 5).trim();
        const elem = context.querySelector(outside);
        if ( elem === null ) { return null; }
        const shadowRoot = getShadowRoot(elem);
        return shadowRoot && querySelectorEx(inside, shadowRoot);
    };

    const selectorList = safe.String_split.call(selectors, /\s*,\s*/)
        .filter(s => {
            try {
                void querySelectorEx(s);
            } catch {
                return false;
            }
            return true;
        });
    if ( selectorList.length === 0 ) { return; }

    const clickDelay = parseInt(delay, 10) || 1;
    const t0 = Date.now();
    const tbye = t0 + 10000;
    let tnext = selectorList.length !== 1 ? t0 : t0 + clickDelay;

    const terminate = ( ) => {
        selectorList.length = 0;
        next.stop();
        observe.stop();
    };

    const next = notFound => {
        if ( selectorList.length === 0 ) {
            safe.uboLog(logPrefix, 'Completed');
            return terminate();
        }
        const tnow = Date.now();
        if ( tnow >= tbye ) {
            safe.uboLog(logPrefix, 'Timed out');
            return terminate();
        }
        if ( notFound ) { observe(); }
        const delay = Math.max(notFound ? tbye - tnow : tnext - tnow, 1);
        next.timer = setTimeout(( ) => {
            next.timer = undefined;
            process();
        }, delay);
        safe.uboLog(logPrefix, `Waiting for ${selectorList[0]}...`);
    };
    next.stop = ( ) => {
        if ( next.timer === undefined ) { return; }
        clearTimeout(next.timer);
        next.timer = undefined;
    };

    const observe = ( ) => {
        if ( observe.observer !== undefined ) { return; }
        observe.observer = new MutationObserver(( ) => {
            if ( observe.timer !== undefined ) { return; }
            observe.timer = setTimeout(( ) => {
                observe.timer = undefined;
                process();
            }, 20);
        });
        observe.observer.observe(document, {
            attributes: true,
            childList: true,
            subtree: true,
        });
    };
    observe.stop = ( ) => {
        if ( observe.timer !== undefined ) {
            clearTimeout(observe.timer);
            observe.timer = undefined;
        }
        if ( observe.observer ) {
            observe.observer.disconnect();
            observe.observer = undefined;
        }
    };

    const process = ( ) => {
        next.stop();
        if ( Date.now() < tnext ) { return next(); }
        const selector = selectorList.shift();
        if ( selector === undefined ) { return terminate(); }
        const elem = querySelectorEx(selector);
        if ( elem === null ) {
            selectorList.unshift(selector);
            return next(true);
        }
        safe.uboLog(logPrefix, `Clicked ${selector}`);
        elem.click();
        tnext += clickDelay;
        next();
    };

    runAtHtmlElementFn(process);
}

/******************************************************************************/

builtinScriptlets.push({
    name: 'trusted-replace-outbound-text.js',
    requiresTrust: true,
    fn: trustedReplaceOutboundText,
    dependencies: [
        'proxy-apply.fn',
        'safe-self.fn',
    ],
});
function trustedReplaceOutboundText(
    propChain = '',
    rawPattern = '',
    rawReplacement = '',
    ...args
) {
    if ( propChain === '' ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('trusted-replace-outbound-text', propChain, rawPattern, rawReplacement, ...args);
    const rePattern = safe.patternToRegex(rawPattern);
    const replacement = rawReplacement.startsWith('json:')
        ? safe.JSON_parse(rawReplacement.slice(5))
        : rawReplacement;
    const extraArgs = safe.getExtraArgs(args);
    const reCondition = safe.patternToRegex(extraArgs.condition || '');
    proxyApplyFn(propChain, function(context) {
        const encodedTextBefore = context.reflect();
        let textBefore = encodedTextBefore;
        if ( extraArgs.encoding === 'base64' ) {
            try { textBefore = self.atob(encodedTextBefore); }
            catch { return encodedTextBefore; }
        }
        if ( rawPattern === '' ) {
            safe.uboLog(logPrefix, 'Decoded outbound text:\n', textBefore);
            return encodedTextBefore;
        }
        reCondition.lastIndex = 0;
        if ( reCondition.test(textBefore) === false ) { return encodedTextBefore; }
        const textAfter = textBefore.replace(rePattern, replacement);
        if ( textAfter === textBefore ) { return encodedTextBefore; }
        safe.uboLog(logPrefix, 'Matched and replaced');
        if ( safe.logLevel > 1 ) {
            safe.uboLog(logPrefix, 'Modified decoded outbound text:\n', textAfter);
        }
        let encodedTextAfter = textAfter;
        if ( extraArgs.encoding === 'base64' ) {
            encodedTextAfter = self.btoa(textAfter);
        }
        return encodedTextAfter;
    });
}

/*******************************************************************************
 * 
 * Reference:
 * https://github.com/AdguardTeam/Scriptlets/blob/5a92d79489/wiki/about-trusted-scriptlets.md#trusted-suppress-native-method
 * 
 * This is a first version with current limitations:
 * - Does not support matching arguments which are object or array
 * - Does not support `stack` parameter
 * 
 * If `signatureStr` parameter is not declared, the scriptlet will log all calls
 * to `methodPath` along with the arguments passed and will not prevent the
 * trapped method.
 * 
 * */

builtinScriptlets.push({
    name: 'trusted-suppress-native-method.js',
    requiresTrust: true,
    fn: trustedSuppressNativeMethod,
    dependencies: [
        'matches-stack-trace.fn',
        'proxy-apply.fn',
        'safe-self.fn',
    ],
});
function trustedSuppressNativeMethod(
    methodPath = '',
    signature = '',
    how = '',
    stack = ''
) {
    if ( methodPath === '' ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('trusted-suppress-native-method', methodPath, signature, how, stack);
    const signatureArgs = safe.String_split.call(signature, /\s*\|\s*/).map(v => {
        if ( /^".*"$/.test(v) ) {
            return { type: 'pattern', re: safe.patternToRegex(v.slice(1, -1)) };
        }
        if ( /^\/.+\/$/.test(v) ) {
            return { type: 'pattern', re: safe.patternToRegex(v) };
        }
        if ( v === 'false' ) {
            return { type: 'exact', value: false };
        }
        if ( v === 'true' ) {
            return { type: 'exact', value: true };
        }
        if ( v === 'null' ) {
            return { type: 'exact', value: null };
        }
        if ( v === 'undefined' ) {
            return { type: 'exact', value: undefined };
        }
    });
    const stackNeedle = safe.initPattern(stack, { canNegate: true });
    proxyApplyFn(methodPath, function(context) {
        const { callArgs } = context;
        if ( signature === '' ) {
            safe.uboLog(logPrefix, `Arguments:\n${callArgs.join('\n')}`);
            return context.reflect();
        }
        for ( let i = 0; i < signatureArgs.length; i++ ) {
            const signatureArg = signatureArgs[i];
            if ( signatureArg === undefined ) { continue; }
            const targetArg = i < callArgs.length ? callArgs[i] : undefined;
            if ( signatureArg.type === 'exact' ) {
                if ( targetArg !== signatureArg.value ) {
                    return context.reflect();
                }
            }
            if ( signatureArg.type === 'pattern' ) {
                if ( safe.RegExp_test.call(signatureArg.re, targetArg) === false ) {
                    return context.reflect();
                }
            }
        }
        if ( stackNeedle.matchAll !== true ) {
            const logLevel = safe.logLevel > 1 ? 'all' : '';
            if ( matchesStackTraceFn(stackNeedle, logLevel) === false ) {
                return context.reflect();
            }
        }
        if ( how === 'debug' ) {
            debugger; // eslint-disable-line no-debugger
            return context.reflect();
        }
        safe.uboLog(logPrefix, `Suppressed:\n${callArgs.join('\n')}`);
        if ( how === 'abort' ) {
            throw new ReferenceError();
        }
    });
}

/*******************************************************************************
 * 
 * Trusted version of prevent-xhr(), which allows the use of an arbitrary
 * string as response text.
 * 
 * */

builtinScriptlets.push({
    name: 'trusted-prevent-xhr.js',
    requiresTrust: true,
    fn: trustedPreventXhr,
    dependencies: [
        'prevent-xhr.fn',
    ],
});
function trustedPreventXhr(...args) {
    return preventXhrFn(true, ...args);
}

/**
 * @trustedScriptlet trusted-prevent-dom-bypass
 * 
 * @description
 * Prevent the bypassing of uBO scriptlets through anonymous embedded context.
 * 
 * Ensure that a target method in the embedded context is using the
 * corresponding parent context's method (which is assumed to be
 * properly patched), or to replace the embedded context with that of the
 * parent context.
 * 
 * Root issue:
 * https://issues.chromium.org/issues/40202434
 * 
 * @param methodPath
 * The method which calls must be intercepted. The arguments
 * of the intercepted calls are assumed to be HTMLElement, anything else will
 * be ignored.
 * 
 * @param [targetProp]
 * The method in the embedded context which should be delegated to the
 * parent context. If no method is specified, the embedded context becomes
 * the parent one, i.e. all  properties of the embedded context will be that
 * of the parent context.
 * 
 * @example
 * ##+js(trusted-prevent-dom-bypass, Element.prototype.append, open)
 * 
 * @example
 * ##+js(trusted-prevent-dom-bypass, Element.prototype.appendChild, XMLHttpRequest)
 * 
 * */

builtinScriptlets.push({
    name: 'trusted-prevent-dom-bypass.js',
    requiresTrust: true,
    fn: trustedPreventDomBypass,
    dependencies: [
        'proxy-apply.fn',
        'safe-self.fn',
    ],
});
function trustedPreventDomBypass(
    methodPath = '',
    targetProp = ''
) {
    if ( methodPath === '' ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('trusted-prevent-dom-bypass', methodPath, targetProp);
    proxyApplyFn(methodPath, function(context) {
        const elems = new Set(context.callArgs.filter(e => e instanceof HTMLElement));
        const r = context.reflect();
        if ( elems.length === 0 ) { return r; }
        for ( const elem of elems ) {
            try {
                if ( `${elem.contentWindow}` !== '[object Window]' ) { continue; }
                if ( elem.contentWindow.location.href !== 'about:blank' ) {
                    if ( elem.contentWindow.location.href !== self.location.href ) {
                        continue;
                    }
                }
                if ( targetProp !== '' ) {
                    let me = self, it = elem.contentWindow;
                    let chain = targetProp;
                    for (;;) {
                        const pos = chain.indexOf('.');
                        if ( pos === -1 ) { break; }
                        const prop = chain.slice(0, pos);
                        me = me[prop]; it = it[prop];
                        chain = chain.slice(pos+1);
                    }
                    it[chain] = me[chain];
                } else {
                    Object.defineProperty(elem, 'contentWindow', { value: self });
                }
                safe.uboLog(logPrefix, 'Bypass prevented');
            } catch {
            }
        }
        return r;
    });
}

/**
 * @trustedScriptlet trusted-override-element-method
 * 
 * @description
 * Override the behavior of a method on matching elements.
 * 
 * @param methodPath
 * The method which calls must be intercepted.
 * 
 * @param [selector]
 * A CSS selector which the target element must match. If not specified,
 * the override will occur for all elements.
 * 
 * @param [disposition]
 * How the override should be handled. If not specified, the overridden call
 * will be equivalent to an empty function. If set to `throw`, an exception
 * will be thrown. Any other value will be validated and returned as a
 * supported safe constant.
 * 
 * @example
 * ##+js(trusted-override-element-method, HTMLAnchorElement.prototype.click, a[target="_blank"][style])
 * 
 * */

builtinScriptlets.push({
    name: 'trusted-override-element-method.js',
    requiresTrust: true,
    fn: trustedOverrideElementMethod,
    dependencies: [
        'proxy-apply.fn',
        'safe-self.fn',
        'validate-constant.fn',
    ],
});
function trustedOverrideElementMethod(
    methodPath = '',
    selector = '',
    disposition = ''
) {
    if ( methodPath === '' ) { return; }
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('trusted-override-element-method', methodPath, selector, disposition);
    const extraArgs = safe.getExtraArgs(Array.from(arguments), 3);
    proxyApplyFn(methodPath, function(context) {
        let override = selector === '';
        if ( override === false ) {
            const { thisArg } = context;
            try {
                override = thisArg.closest(selector) === thisArg;
            } catch {
            }
        }
        if ( override === false ) {
            return context.reflect();
        }
        safe.uboLog(logPrefix, 'Overridden');
        if ( disposition === '' ) { return; }
        if ( disposition === 'debug' && safe.logLevel !== 0 ) {
            debugger; // eslint-disable-line no-debugger
        }
        if ( disposition === 'throw' ) {
            throw new ReferenceError();
        }
        return validateConstantFn(true, disposition, extraArgs);
    });
}

/******************************************************************************/