Thunar automatically restores cleared default shortcuts

I cleared the default Undo and Redo shortcuts several times in the past two weeks, because Thunar reverts my shortcut changes from time to time. I don't know at which point it does so (this does not happen when I quit or end the thunar process, then start it again).

Steps to reproduce:

1. Clear Undo and Redo shortcuts in File Manager Preferences => Shortcuts.
2. Use Thunar for a few days, log out, log in, reboot, etc.

Actual results: Eventually the default shortcuts are going to be assigned again without a user request or consent.

Expected results: The default shortcuts remain cleared until the user explicitly restores them.