The save-with-user-input flow requires a widget to parent it's potential messages and other widgets to, but when we're closing the application no such potential widgets exists anymore, leading to a crash.
Therefore, we'll just save the palette regularly, but only if it already has a resource-version. I don't think it's currently possible to have a palette without resource version, so that should suffice.
This also seems to fix actually saving the resource upon close, which was the original bug to begin with.
I ended up throwing some debug into the debug field as well, to ensure anyone playing with the log docker is informed.