ZenFox by Sanjay

ZenFox turns Firefox's sidebar into a calm, Zen Browser–style home for your tabs. Group everything you do into workspaces — Personal, Work, Reading, Travel — and switch between them with one click or a keyboard shortcut. Tabs from other workspaces stay out of the way, even in Ctrl+Tab.

Organize
* Essentials: up to 12 favorite sites as icon tiles, available in every workspace.
* Pinned tabs per workspace with custom names and a home URL you can always reset to.
* Folders (Firefox tab groups) inside a workspace, collapsible from the sidebar.
* Drag tabs to reorder, pin, unpin, make Essential, or move them to another workspace. Select several with Ctrl/⌘-click or Shift-click and act on them together.
* Give each workspace an emoji, a theme color, or the icon of any website.

Move fast
* Command palette (Alt+K, ⌘⇧Space on Mac): search open tabs in every workspace and window, bookmarks, history and recently closed tabs, or run commands like “Move tab to…”, “Snapshot workspace” and “Clear”.
* Keyboard shortcuts for switching workspaces; more commands (workspace 1–9, pin, sleep, copy URL, restore closed tab) can be assigned in Firefox's shortcut settings.
* Routing rules: always open a site in a chosen workspace (and, if you turn it on, sites that share a workspace's name).
* Open any link in a workspace from the right-click menu.

Stay tidy
* Clear closes all unpinned tabs in a workspace, with Undo.
* Recently closed per workspace, and snapshots to save a whole workspace, close it and bring it back later.
* Optional automatic sleep for idle tabs and automatic archiving of old unpinned tabs.
* Cleaner tab titles (removes “ - Site name” suffixes and unread counters), with rules you can edit.
* Optional Firefox container per workspace, so each workspace keeps its own logins and cookies.

Make it look like Zen (optional)
Settings → "Hide Firefox top tab bar" gives you a one-step installer that hides Firefox's horizontal tab strip and can collapse the sidebar into an icon rail that expands on hover. It adds one line to your profile's userChrome.css and keeps (and backs up) your own customizations.

Private by design
ZenFox has no servers, no accounts, no analytics and no remote code. Everything is stored locally in your Firefox profile. Pages from private windows are never written to disk.

Why these permissions?
* Tabs, hide tabs, recently closed tabs: show and switch workspaces, keep other workspaces out of Ctrl+Tab, restore tabs after a restart and for Undo.
* Bookmarks, history, downloads: the Library panel and palette search.
* Clipboard: the "Copy URL" command and copying the layout installer.
* Containers / cookies: only used if you assign a container to a workspace.
* Access to all websites is not requested at install. It is only asked for if you turn on the optional on-page shortcut fallback.

Feedback and bug reports are welcome on the support site below.