I'm referring to holding Ctrl and hitting Menu (which is this key), which happens by mistake sometimes.

For me it results in going back to normal mode and moving to the first non-blank character of the line.

Indeed, if I hit Ctrl+v and then Ctrl+Menu (in command line mode or insert mode), what I see is ^[[29^, where the first two chars ^[ are one atom (the same that is generated also by Escape), and the following are single chars. So I kind of understand why the combination reults in "go back to normal mode, ^[, and then to the first non-blank character, ^.

But how can I get rid of this behavior without impacting anything else?