Keep native Chromium loading and prevent stale browser cache entries

frontend/lazy.js

@@ -124,7 +124,9 @@
   };
   // Own this response once. Classic-script and fetch preloads do not share
   // their cached bodies in WebKit; the later bootstrap consumes this promise.
-  if(manifest.appCache && root.crypto?.subtle) {
+  const agent=root.navigator.userAgent || '';
+  api.captureApp=!!(manifest.appCache && root.crypto?.subtle && /AppleWebKit\//.test(agent) && !/(?:Chrome|Chromium|Edg|OPR)\//.test(agent));
+  if(api.captureApp) {
     api.appResponse=(async()=>{
       const key=url('/app.js');
       try {
@@ -134,6 +136,9 @@
       return root.fetch(key,{credentials:'same-origin'});
     })();
     api.appResponse.catch(()=>{});
+  } else if(manifest.appCache) {
+    // Preserve native script/code-cache reuse in engines without the WebKit gap.
+    const preload=doc.createElement('link');preload.rel='preload';preload.as='script';preload.href=url('/app.js');doc.head.append(preload);
   }
   root.Lazy = api;
   root.navigator.serviceWorker?.addEventListener('message',event=>{