[mayakwd]

Issue
While no ouput is connected, windows live in the workspaces.backup_set, but Shell:unmap_surface searches only workspace.sets. So, a window unmapped in that state will never be removed from the shell and never reach remove_toplevel.

It leads to two discrepancies:

• it stays listed as toplevel - a "ghost" in the dock and launcher (switcher)
• it's being added again one an output is reconnected

The fix
Just unmap surface from backup_set as well.

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[Drakulix]

Makes sense. Thx!

[mayakwd]

Conflicts are resolved, the code stays the same.
Unfortunately, as a result approves were dismissed :-)