Mnemonics cannot be disabled in context menu's of items on the desktop or Nemo

Distribution

Mint 22.1

Package version

Cinnamon 6.4.8

Graphics hardware in use

No response

Frequency

Always

Bug description

Came across someone with this problem on Reddit, tried to reproduce and can confirm it.

Right clicking on an item on the desktop or in Nemo, and then activating mnemonics through the ALT key shows the mnemonics. But then trying to hide them again by pressing ALT key again does not work: the mnemonics are permanently shown. In contrast, when right clicking on a window and then activating mnemonics through the ALT key, pressing ALT again disables the mnemonics as it should.

Steps to reproduce

1. Right click on an item on the desktop or in nemo
2. Press ALT to activate mnemonics
3. Press ALT again to try to disable mnemonics
4. Mnemonics don't go away

Expected behavior

1. Right click on an item on the desktop or in nemo
2. Press ALT to activate mnemonics
3. Press ALT again to disable mnemonics
4. Mnemonics go away

Additional information

https://www.reddit.com/r/linuxmint/s/3VSsIwVonQ

Original poster of this bug on Reddit

No source file or test is named. Start by reproducing the issue in Cinnamon 6.4.8 on Mint 22.1, using both desktop and Nemo item context menus, then compare their mnemonic handling with a window context menu. Done means pressing Alt twice hides the mnemonics in both affected menus.