What works where — and the known gaps per browser.

Hacklets is built for Chrome (and Chromium browsers such as Edge) and works partially in Firefox.

Safari is not supported at this stage.

Compatibility matrix

FeatureChrome / EdgeFirefox
Bookmark search
Built-in commands
Bookmarklet runner
User Scripts (local folder)
New tab palette
Favicon icons✅ native✅ via Google service

Feature support are detected at runtime, so a browser release that gains a capability will likely pick it up automatically.

Firefox gaps

No filesystem access for User Scripts

Firefox doesn’t support the File System Access API, so pointing Hacklets at a local folder of scripts is unavailable. The rest of the extension still works.

Restricted domains

Firefox refuses to inject content scripts on certain Mozilla-controlled domains (configured in extensions.webextensions.restrictedDomains in about:config). On pages like addons.mozilla.org or accounts.firefox.com the palette shortcut fires but nothing appears, because the content script can’t load. This is a deliberate browser restriction, not a Hacklets bug.

Favicons over the network

Without a native chrome://favicon/ API, Firefox fetches favicons from https://www.google.com/s2/favicons, sending each bookmark’s hostname to Google. Results are cached locally. See the Privacy Policy.

Safari notes

Safari is unsupported at this stage. The WebExtension APIs support is limited and may require workarounds.

Stale folder listings (all browsers)

The File System Access API returns a cached directory snapshot, so newly added or renamed files may not appear in the palette immediately. Re-pick the folder for a fresh handle, or accept the brief delay — Chrome syncs its cache periodically. Script execution always reads the latest code from disk.