Tab Groups Switcher

A compact Firefox WebExtension for quickly switching between currently open Firefox tab groups.

By default, the popup shows only open tab groups. Remembered closed tab groups are an experimental opt-in feature for people who want the extension to recreate groups it has previously tracked.

Firefox does not currently expose native saved tab groups to WebExtensions. When remembered closed groups are enabled, the extension recreates them from stored URLs instead of reopening Firefox's native saved group identity. This will duplicate Firefox's own saved groups when those saved groups still exist.

Install for Testing

1. Open Firefox and go to about:debugging.
2. Select This Firefox.
3. Click Load Temporary Add-on....
4. Choose manifest.json from this folder.
5. Use the Tab Groups Switcher toolbar button to open the popup.

Manual Test Checklist

1. Create one or more Firefox tab groups.
2. Open the toolbar popup and confirm each exposed group appears in one flat list with its color and title.
3. Click an open group and confirm Firefox focuses that window, expands the group if needed, and activates a tab in the group.
4. Close or save a group after it has been seen by the extension.
5. Reopen the popup and confirm the remembered closed group is hidden by default.
6. Open the extension options page and enable Show remembered closed tab groups.
7. Reopen the popup and confirm the remembered group appears with an outlined color dot and does not duplicate any currently open group.
8. Click the remembered group and confirm its tabs reopen in a recreated tab group with the saved title and color.
9. Disable Show remembered closed tab groups and confirm remembered groups are hidden again.
10. Open the extension options page and confirm tracked groups can be reordered by dragging their handles.
11. Confirm Minimize other tab groups when switching is enabled, switch groups from the popup, and confirm other open groups collapse while ungrouped tabs remain open.
12. Uncheck Auto-collapse for one tracked group, switch to another group from the popup, and confirm the unchecked group stays expanded.

If the popup says Firefox tab group extension APIs are not available in this browser version., update Firefox to a version that supports the browser.tabGroups WebExtensions API.

Default Behavior

The extension is primarily a switcher for open Firefox tab groups. On a fresh install, the toolbar popup lists only groups currently exposed by Firefox through the browser.tabGroups API. Clicking a group focuses its window, expands the group if needed, and activates a tab in that group.

The popup respects the saved manual order for tracked groups. Open groups that match a tracked group use that saved order, while open groups that have not been tracked yet appear after ordered groups.

Experimental Remembering

The background script watches tab group and tab lifecycle events, then snapshots every visible/open tab group with its title, color, ordered URLs, ordered tab titles, and timestamps. Remembered groups are stored in browser.storage.local and keep a manual order value for the popup.

Remembered closed groups stay hidden unless Show remembered closed tab groups is enabled in options. When enabled, the popup shows open groups with filled color dots and remembered closed groups with outlined color dots. When a currently open group matches a remembered group, the popup hides the remembered duplicate and clicking that row focuses the open group.

Matching favors exact URL signatures, then normalized group names plus URL overlap. This avoids relying on Firefox group IDs being stable across sessions.

Options

Open the extension options page to manage switching and remembered group visibility:

• Reorder with drag and drop.
• Toggle whether switching to a group minimizes other currently open tab groups.
• Uncheck Auto-collapse for tracked groups that should stay expanded during switch actions.
• Toggle whether remembered closed tab groups appear in the popup.

The tracked group list includes a drag handle for ordering and an Auto-collapse checkbox for per-group switching behavior.

Switching Behavior

By default, switching groups first focuses or recreates the selected group, then collapses the other open tab groups. Ungrouped tabs are not changed. Disable Minimize other tab groups when switching if you want other open groups to stay expanded. To keep only specific tracked groups expanded during switch actions, uncheck Auto-collapse for those groups in options.

Restore Behavior

Firefox does not expose native saved tab groups directly to WebExtensions, and the supported sessions API exposes recently closed entries as tabs or windows rather than tab group records. Because of that, the extension cannot reopen a specific native saved tab group by identity.

When remembered closed groups are enabled and you click a remembered group, the extension first checks whether an equivalent group is already open and focuses it. If it is closed, the extension recreates the group from the URLs it previously remembered, then reconciles the new live group back into the existing remembered record so the popup does not show duplicate entries.

Development

To create a zip archive for uploading to the Add-on Developer Hub:

rm ../tab-groups-switcher.zip && \
zip -r ../tab-groups-switcher.zip \
  manifest.json \
  background.js \
  popup.html \
  popup.css \
  popup.js \
  options.html \
  options.css \
  options.js \
  README.md \
  icons

Limitations

This extension does not read Firefox profile files, inspect sessionstore internals, use native messaging, or call undocumented APIs. It can only recreate groups that it previously saw while they were open and exposed by Firefox.

Bugzilla Tracking

• Bug 1940631: Implement tabGroups WebExtensions API
• Bug 1927769: Allow sessions.restore to understand tab groups
• Bug 1968190: Closed grouped tabs and restore add-ons
• Bug 1979759: Saved-and-closed groups in Recently Closed Tabs