@Vierkantor 1. Security when you really need the window gone: Just add another shortcut to make it permanently gone. Having this option system-wide and unified might actually offer better security than what we have now, where some apps can undo closing windows/tab but they aren't consistent with each other.
@Vierkantor 2. Unsaved changes: This is an artefact of an older age when saving was expensive. We can auto-save now. If it's an incomplete thing, save it as a draft. Just make it always safe to close the window. As a bonus, this can prevent data loss during a crash!
A Mastodon instance specializing in Vocaloid, UTAU, and anything relevant to vocalsynth culture.