Keyboard-first session management for Firefox. Save and restore windows and tabs — with fast multi-select, full keyboard navigation, and tab-group awareness for wrangling large numbers of saved sessions.
Tab Session Garrison is a personal fork of Tab Session Manager by Sienori, focused on power-user controls: selecting, navigating, restoring, and deleting sessions without leaving the keyboard — and clearing out the noise that builds up when you auto-save constantly.
Everything Tab Session Manager does — save and restore the state of windows and tabs, automatic timed saving, tagging, search, import/export, and native tab-group save/restore — plus:
- Multi-select sessions with Ctrl/Cmd-click, Shift-click ranges, or the keyboard
- Full keyboard navigation — the list, search, the tab list, menus and dialogs all work from the keyboard, with a ? cheat sheet in the popup (see the keyboard reference)
- Bulk delete with a single "undo all" — clear out dozens of stale auto-saves at once, and still get them back if you misclick
- Bulk restore — open every selected session at once, each in its own new window (with a confirm so a stray keypress doesn't flood your screen)
- An "N selected" summary panel — with Open all and Delete actions — so you always know what a bulk action will hit
- Group indicators — every session shows its Firefox tab groups at a glance: colored, named chips in the detail pane, colored dots on each list row, and in the tab list each group's tabs carry the group's colour and name
- Add a session to your current window as a tab group — drop a saved session's tabs into the window you're in, tidied into one named group (and it preserves the session's own groups when it already has them)
- Phantom-group masking — older auto-saves that captured stray groups from other windows are cleaned up at display time, non-destructively
- Exact phrases — put words in quotes (
"release notes") to find that phrase inside a single tab title, session name or group name. Without quotes, each word can match anywhere in the session. An unfinished quote counts as a phrase while you type, and curly quotes work too - Tab-group names are searchable — type a group's name to find every session that contains it
- Matches are highlighted in the list and in the detail pane, and the filter menu shows how many sessions match (
All [3/20])
- Failed saves are visible — if saving ever fails (a full disk, a broken database), a red ! appears on the toolbar icon and the popup says since when and why, instead of auto-save quietly stopping (upstream #1667). The next successful save clears it
- Says why a tab couldn't open — the "This page can not be opened" placeholder now shows Firefox's reason, e.g. "Illegal URL"
- Device name in backup file names — optional, so backups from several computers sharing one folder can be told apart (upstream #1664)
- Durable auto-save — fixes an upstream bug where periodic auto-save could silently stop after the browser suspended or restarted; the alarm now self-heals
- Session types at a glance — every session shows how it was saved, each with its own icon and tint: Manual Save (green bookmark), Regularly (blue clock), Window closed (amber window), Browser exited (red power). The saves you deliberately keep finally stand out from the auto-save noise (see How a session gets its type)
- Undo count at a glance — the undo/redo buttons carry a small badge with how many steps you can go back or forward
- Add several tags at once — type
work, reading, laterin Add Tag and each becomes its own tag - Imports always show up — sessions exported with the internal "temp" marker used to import invisibly (upstream #1502); the marker is now dropped on import
- Restore respects your settings — with Save tab groups turned off, restoring a session no longer recreates (and thereby re-saves) the tab groups you opted out of; tabs come back flat (upstream #1635)
- A cohesive visual identity — its own green session-stack logo and a boxed "card" layout across the popup and options pages, with one consistent green accent, pill buttons, and dark theme by default. In Settings, the section you're scrolled to is spotlighted while the rest dims, so a long settings page stops feeling like a wall
The popup was reworked to stay responsive when you've got hundreds — or thousands — of saved sessions:
- Instant list interactions — selecting, searching, and arrow-keying no longer walk the whole list on every keystroke; per-row array scans were replaced with
Map/Setlookups - Off-screen rows cost nothing —
content-visibilitylets the browser lay out and paint only the rows actually on screen, deferring the rest until you scroll to them - Near-instant bulk delete — deleting dozens of sessions used to rewrite the whole (favicon-heavy) undo history once per session; it's now a single batched write with one screen update
- The list paints at once — the first rows appear immediately and the rest fill in without blocking, so a 3,500-session profile opens in about a quarter of a second
- No favicon memory build-up — favicons are shrunk without creating throwaway Blobs, which Firefox was slow to free; on busy profiles the background page used to grow by hundreds of MB (port of upstream PR #1663)
- A session index — the list and search read a small index kept alongside your sessions, instead of decoding every full session (every tab and favicon) each time the popup opens. On a 3,500-session profile that's under 1 MB read instead of ~38 MB decoded twice; the full record is loaded only for the session you select. Auto-save's background bookkeeping reads the same index
Every session is one of four types, shown as a coloured pill:
| Pill | Meaning |
|---|---|
| 📑 Manual Save (green) | You saved it yourself — the Save button or the keyboard shortcut |
| Regularly (blue) | The timed auto-save |
| Window closed (amber) | Captured automatically when you closed a window |
| Browser exited (red) | Captured automatically when Firefox last quit |
The three automatic types carry a stored marker, so they're always exact. Manual Save is stamped on every save you make from now on. For older sessions saved before this feature — and for anything imported that arrived without a type — it's inferred from the absence of an auto-save marker. In practice that inference is accurate: a session you manually saved in Tab Session Manager and imported here still reads as a Manual Save. The type pills are descriptors, not labels, so they can't be removed — but your own custom tags still can.
Everything works without the mouse. Press ? in the popup for this list, or see Settings → Shortcuts. Both come from one list in the code (src/common/keymap.js), and tools/screenshots/keytest.js presses every key before a release.
Session list
| Keys | Action |
|---|---|
| ↑ ↓ Home End PgUp PgDn | Move the selection |
| Shift + the same keys | Extend the selection |
| Space | Add or remove the session from the selection |
| Ctrl/⌘ + A | Select all visible sessions (respects filter and search) |
| Esc | Back to a single selection |
| Enter | Open (several: each in its own new window, after a confirm) |
| Ctrl/⌘ + Enter | Open in the current window, replacing its tabs |
| Alt + Enter | Add to the current window |
| Delete / Backspace | Delete the selection (confirms when more than one) |
| F2 | Rename the session |
| Shift + F2 | Add tags |
| Shift + F10 / Menu key | Open the session menu |
| → | Move into the tab list |
| / or just start typing | Search (" starts a phrase) |
Search box: Enter or ↓ goes to the first result; Esc clears the search, then closes it.
Tab list: ↑ ↓ Home End move between tabs, Enter opens the tab, Delete removes it from the session, ← or Esc goes back to the session list.
Menus and dialogs: ↑ ↓ move between menu items, Esc closes.
Anywhere in the popup: Ctrl/⌘ + Z undo, Ctrl/⌘ + Shift + Z (or Ctrl + Y) redo, ? shows the list of keys, Tab / Shift + Tab move between the list, the search box and the save box.
Mouse: Ctrl/⌘ + click toggles one session in or out of the selection; Shift + click selects a range.
Browser-wide (change them in Settings → Shortcuts): open the popup (Ctrl+Shift+L by default), save all windows, save the current window, export sessions.
This is a personal fork, built and used on Firefox (Linux). A few things to know:
- Firefox only, for now. This fork targets Firefox and nothing else; Chrome/Edge may come later. If you need those today, the original Tab Session Manager is on the Firefox, Chrome, and Edge stores.
- On addons.mozilla.org. Install it from the store (below); Firefox keeps it updated.
- Local-only by design. No cloud sync, no accounts — the upstream Google Drive sync isn't offered here. Everything lives in your browser, on your machine.
- No telemetry. Sessions are stored by the browser, on your machine.
- Found a bug or have an idea? Open an issue. Please report problems with this fork here, not on the upstream Tab Session Manager tracker.
Get it on addons.mozilla.org — the listed, Mozilla-reviewed build. Firefox keeps it up to date automatically.
Each release's AMO-signed .xpi is also attached to GitHub Releases (install via about:addons → ⚙ → Install Add-on From File). It's the same add-on, so it still gets updates from AMO.
Upgrading from a pre-0.3.0 self-signed build? Nothing to do — it's the same add-on id, so your install moves to the AMO build on its next update check and keeps all your sessions and settings.
- Build it (see Developing), or use an existing
dev/firefoxbuild. - Firefox →
about:debugging#/runtime/this-firefox→ Load Temporary Add-on → pickmanifest.jsoninsidedev/firefox.
Temporary add-ons unload when Firefox restarts. The cut-a-release procedure (version bump, build, AMO submission, GitHub mirror) lives in RELEASING.md.
Node 22+ / npm 10+. The production build is deterministic — see BUILD.md.
git clone https://github.com/superuser-miguel/Tab-Session-Garrison
cd Tab-Session-Garrison
npm install
npm run watch-dev # rebuilds on save; output lands in dev/firefoxLoad dev/firefox/manifest.json via about:debugging (see Installing).
In progress
- Backup overhaul — the original backup was a single confusing toggle that dumped one unpruned file per auto-save (tens of thousands of them, forever). Replacing it with a clear three-tier engine, all under the download folder, that never deletes your history and uses zip compression to manage space instead:
- Complete — a full, compressed snapshot of every session, kept indefinitely for disaster recovery (built)
- Session — one file per saved session, updated in place (next)
- Incremental — append-only point-in-time history of auto-saves; recent snapshots stay as loose, browsable files and older ones roll up into zips once a date/size threshold is hit (next)
- Restore-from-backup UI — browse and restore snapshots without hand-importing files (after the engine)
- Tab Groups polish — group save/restore, on-demand grouping, and visual indicators are in; still hardening edge cases (restoring into windows that already have groups, multi-window merges)
Planned
- Firefox Split View — investigated (Jul 2026): Firefox does expose split state (each tab carries a
splitViewId), and Tab Session Garrison already captures it when you save. Restoring a split isn't possible yet — Firefox has no API to create a split from an extension (bug 2016928 / WECG #967). Once that ships, restore drops in with no re-work - Search overhaul — phase 1 started:
"quoted phrases"are in. Next: search site names and tags,-excludewords, and filters likesite:,tag:andgroup:; then fuzzy matching in the spirit of fzf (ghb→ GitHub) with results ranked by match quality; then a "why it matched" hint on each row - Rename saved windows — give each window in a saved session its own editable name, right where you'd expect it: the pencil / right-click menu already on every window header in the detail pane (today that menu only offers "add current tab"). Firefox has no reliable window-name API to capture from, so an in-app rename is the robust answer — and it's the natural home for defaulting a window's name to its tab group's name when the window is a single group
- Trash can — deleted sessions go to a recoverable trash instead of vanishing once the undo window passes; restore or empty it on your terms
- UI refresh — largely shipped: the popup and options pages now share a green "card" system, pill buttons, dark-by-default theming, and a scroll-focus Settings view. Still to come: a fixed "window" frame for the settings focus view, finishing the theme-follows-Firefox popup, and reworking the Import Sessions screen so a large import is a scrollable list you can remove individual entries from before committing (instead of all-or-nothing)
- Import a URL list into a tab group — paste a plain list of URLs and turn it into a saved session (optionally opened as one named tab group), OneTab-style
- Save & close (stash) — a one-gesture "send this window to a session" that saves the current window and closes its tabs to clear clutter and free memory — OneTab's signature move — with an optional restore-and-remove mode for a true one-shot stash
- Pin & lock sessions — star a session to keep it at the top, and lock it so it can't be deleted by accident (OneTab star/lock); pairs naturally with the Trash can
- Share a session as a link list — copy or export a saved session as a plain URL / Markdown list (the reverse of the URL-list import), generated locally with no server
- Duplicate cleanup — collapse the near-identical snapshots that pile up from frequent auto-saving
- Chrome / Edge — possibly, further down the line
Tab Session Garrison stands entirely on Tab Session Manager by Sienori (forked at v7.3.0) — all of the core functionality is theirs. If you want a polished, signed, cross-browser, actively maintained session manager, install the original. This fork just adds keyboard ergonomics and tab-group niceties on top.
Tab Session Garrison is free software, licensed under the GNU General Public License v3.0 or later.
It's a fork of Tab Session Manager © 2017– Sienori, originally released under the Mozilla Public License 2.0. Because the upstream code carries no "Incompatible With Secondary Licenses" notice, MPL-2.0 permits this fork to be distributed under the GPL. Sienori's copyright and the original MPL-2.0 text are preserved in LICENSE.MPL, and the MPL-covered portions remain available under MPL-2.0 as well.
- Upstream code: © 2017– Sienori — MPL-2.0 (see LICENSE.MPL)
- This fork's changes: © 2026 superuser-miguel — GPL-3.0-or-later