Shortcut missing from the shortcut menu

[TimAhrens]

Does my answer on the other thread help?

Custom shortcut issues

In case someone stumbles across this topic as they have the same problem: What seems to work reliably is to explicitly set a different shortcut for “Tidy up Paths” (this is the menu command that has Cmd+Shift+T by default in Glyphs 3, and it seems to be causing the problems). Then adding Cmd+Shift+T for the RMX Tuner should work as you expect.