diff --git a/src/js/assets.js b/src/js/assets.js
index 351cb9d0b..5a550dfb4 100644
--- a/src/js/assets.js
+++ b/src/js/assets.js
@@ -53,10 +53,13 @@ let remoteServerFriendly = false;
 const stringIsNotEmpty = s => typeof s === 'string' && s !== '';
 
 const parseExpires = s => {
-    const matches = s.match(/(\d+)\s*([dhm]?)/i);
+    const matches = s.match(/(\d+)\s*([wdhm]?)/i);
     if ( matches === null ) { return; }
     let updateAfter = parseInt(matches[1], 10);
-    if ( matches[2] === 'h' ) {
+    if ( updateAfter === 0 ) { return; }
+    if ( matches[2] === 'w' ) {
+        updateAfter *= 7 * 24;
+    } else if ( matches[2] === 'h' ) {
         updateAfter = Math.max(updateAfter, 4) / 24;
     } else if ( matches[2] === 'm' ) {
         updateAfter = Math.max(updateAfter, 240) / 1440;