Several MS apps support the concept of chords, like CTRL + X , Y which means “holding down CTRL, press X, then Y“.
Is this a bespoke thing they (and other companies) implement, or is it built into any APIs? It would be nice to be able to set up event handlers or accelerators based on chords rather than write code to do it.
‘Accelerators’ support normal key presses plus any combination of Shift, Ctrl, Alt.
For what you are asking for, I think you would need to process
WM_KEYDOWNandWM_KEYUPyourself.