Space Manager by gaponeni

Space Manager turns Firefox Container Tabs into per-window Spaces.

Use the toolbar popup to switch the active Space for each browser window. The extension reads your existing Firefox containers and uses them as the source of truth, so you keep creating, renaming, and deleting containers in Firefox itself.

What it does
- Lists your existing Firefox containers in the popup.
- Switches the active Space per browser window.
- Shows tabs that belong to the selected container.
- Hides tabs from other Spaces in the same window.
- Restores the last active tab when you return to a Space.
- Preserves tab-group state per Space when tab groups are supported.
- Can recreate some newly opened default-store tabs inside the active container to keep the current window aligned with the selected Space.
- May discard hidden tabs on a best-effort basis to reduce memory usage.

How it works
Space Manager does not create a separate workspace system. It builds on top of Firefox Container Tabs and their cookie-store identities, so your container setup remains native to Firefox.

Privacy
- The add-on does not send browsing data, cookies, or tab metadata to remote servers.
- The add-on does not load or execute remote code.
- In private windows, Space state is kept only for the current private session and is not persisted to extension storage.