On macOS, “Move Tab Left/Right” keybindings do not work

[lexi-lambda]

For some reason, when I type the keybinding in DrRacket for Move Tab Left on my computer, I get an open curly double quote in my buffer instead of actually moving the tab to the left. (Likewise, the keybinding that is supposed to be associated with Move Tab Right types an open curly single quote.)

[Metaxal]

More generally, some keybindings don't seem to work.

For example, I have a menu item bound to 'c:s:t' (from a quickscript). The callback is triggered properly via the menus, but not from the keybinding. The keybinding is shown in the menu and "Enable keybindings in menus" is checked. Show active keybindings also shows the association: .

A wild hypothesis: Could it be related to the fact that I have another keybinding that is a suffix of 'c:s:t'?

Note that many other keybindings work, including from quickscripts.