Palette elements are deleted without any confirm message on palettes created in older versions
OS: Windows 10 (10.0), Arch.: x86_64, MuseScore version (64-bit): 18.104.22.16888, revision: 148e43f.
- Chose a palette with at least one customised symbol in it.
- Delete the symbol.
Expected result: "Are you sure?" window opens, giving user a choice of either archiving the symbol in "More" or deleting permanently.
Actual result: The symbol is permanently deleted without confirmation. No trace in the "More" archive.