Memory leak guard for sidebar extensions

A sidebar extension left open on a heavy page can slowly eat memory until the tab crashes. Reported on a Facebook page, where the sidebar had been open for a while.

The generator should handle this by default rather than leaving each person to find it. That means cleaning up properly when the panel closes or the tab navigates: disconnecting observers, clearing intervals and timeouts, removing event listeners, and releasing anything held in memory between renders.

Right now it can be fixed by asking for it after the fact, which works, but you only know to ask once your tab has already crashed.

Applies to every side panel build, not just one site.

Reported by a customer on 1 Sep 2026.