Jitsi widgets stay running in the background when the widget does not advertise that it should

[turt2live]

Lack of the capability m.always_on_screen doesn't push Jitsi to the sidebar when switching rooms (good), but doesn't cancel the conference either (bad).

[lampholder]

@dbkr could you comment on this?

[dbkr]

It's possible there's a bug where we don't destroy the widget when the AppTile unmounts