Widget Removed is stuck

[René J.V. Bertin]

Bug reports go to bugs.kde.org , with a proper description of exactly what you did, what should have happened and what happened instead. Ideally you'd try at least twice to indicate whether this is a reproducible bug or whether it was a one-time event.

That said, there's a notifications settings panel that you can open in the systemsettings utility; with that you should be able to disable confirmations for widget removal.