diff --git a/platform/mv3/extension/js/scripting-manager.js b/platform/mv3/extension/js/scripting-manager.js
index 6bd20a7e8..6b28dc5b9 100644
--- a/platform/mv3/extension/js/scripting-manager.js
+++ b/platform/mv3/extension/js/scripting-manager.js
@@ -29,8 +29,6 @@ import { ubolLog } from './debug.js';
 
 /******************************************************************************/
 
-const isGecko = browser.runtime.getURL('').startsWith('moz-extension://');
-
 const resourceDetailPromises = new Map();
 
 function getScriptletDetails() {
@@ -467,16 +465,11 @@ function registerScriptlet(context, scriptletDetails) {
                 allFrames: true,
                 matches,
                 excludeMatches,
+                matchOriginAsFallback: true,
                 runAt: 'document_start',
+                world: 'MAIN',
             };
 
-            // https://bugzilla.mozilla.org/show_bug.cgi?id=1736575
-            //   `MAIN` world not yet supported in Firefox
-            if ( isGecko === false ) {
-                directive.world = 'MAIN';
-                directive.matchOriginAsFallback = true;
-            }
-
             // register
             if ( registered === undefined ) {
                 context.toAdd.push(directive);
diff --git a/platform/mv3/firefox/manifest.json b/platform/mv3/firefox/manifest.json
index 7847e3ad5..1ecaad2ec 100644
--- a/platform/mv3/firefox/manifest.json
+++ b/platform/mv3/firefox/manifest.json
@@ -16,10 +16,10 @@
   "browser_specific_settings": {
     "gecko": {
       "id": "uBOLiteRedux@raymondhill.net",
-      "strict_min_version": "127.0"
+      "strict_min_version": "128.0"
     },
     "gecko_android": {
-      "strict_min_version": "127.0"
+      "strict_min_version": "128.0"
     }
   },
   "declarative_net_request": {