A Firefox extension that automatically mutes new tabs. It provides configurable logic for how existing tabs should be handled and whether new tabs should always be muted or only when not matching an exclusion list.
When a tab already exists, the extension can re-mute it under the following conditions:
- Always — Re-mute on any change (reload, URL change)
- On URL Change — Only re-mute when the tab navigates to a different page (simple reloads are ignored)
- Never — Once a tab is unmuted by the user, it stays unmuted regardless of any changes
For newly opened tabs, the extension offers two modes:
- Always — Every new tab is automatically muted
- Exclusion List — New tabs are muted unless their URL matches an entry in the exclusion list
When the exclusion list mode is active, an input field and a scrollable table are displayed. Entries can be added by typing into the input field and pressing Enter. Each entry can be edited or deleted separately. URL matching is case-insensitive and uses substring containment — for example, adding youtube.com will match any URL containing that string.
A quick button is provided to add the current page's domain directly. Browser-specific pages (such as anything under about:) cannot be read by the extension and as such cannot be added to exclusion (as modifying them is not allowed).
Adding or removing an exclusion list entry immediately applies the change to all open tabs — adding an entry unmutes matching tabs, and removing an entry re-mutes them.
The extension supports English and German, selecting the language based on the browser's locale setting.
This extension was written with GLM-5.1 using OpenCode.