Something stealing Ctrl-Y from some apps

[HerbM]

I am virtually certain it is NOT AutoHotKey though i run some macros that are "Window" or "App" specific.

Happens when Autohotkey is disabled (all processes stopped too.) -- unless maybe once loaded the key hook doesn't unload even with AHK stopped????

But I am thinking that maybe autohotkey can help me find the culprit OR work around it.

Usually Ctrl-Y is "redo" (after undo) but this key doesn't seem to be doing ANYTHING in some programs: NotePad++ and PowerShell with PSReadline.

Both have their own significant Key mapping assignments but both clearly show Ctrl-Y is mapped to REDO and no conflicts.

It happens on multiple machines.

It does NOT happen in a CMD.exe console, Slack (app), Firefox, Chrome....

I am running Ditto (which maps some keys) but can't find it there -- and again, nothing happens when it is pressed in the specific apps where it isn't working.

Asking here because you folks likely know the best tools to intercept Windows messages or something and will likely have the most experience and know the most about such issues AND because maybe I can map around the problem.

AHK is showing the Left Cntl-Y in Key history but only shows Right Cntl (no Y) in if I press ctrl on right.

Ideas for finding it? Ideas for mapping around it with Autohotkey?