Status Watch for Firefox

On complex websites with many assets missing files (or URLs with errors) can go unnoticed easily. This is a simple Jetpack that watches HTTP traffic for any responses with 4xx or 5xx response codes and shows a Brief notification to warn the user.

To use the whitelist, add a string named "extensions.statuswatch.whitelist" to about:config. To be as flexible as possible, the string is simply a Regular Expression pattern - if the hostname on the current PaGE matches, the add-on is active for that page and all its assets.