Which back-end? Use the demo window to inspect the inputs that imgui is receiving…
Is the CTRL key received? are the A/C/V keys (not characters) received? etc…
Your back-end is probably not passing them correctly to imgui somehow…
The backend I’m using is OpenGL3 with GLFW, what I found is I swapped CTRL key with Caps Lock so on Demo app it does not detect CTRL at all (it’s mapped on language change) and Caps Lock is detected as just a code 280 without a modifier, that’s why the combinations didn’t work.
Which I think is the same as setxkbmap -option ctrl:nocaps, which is a way the X Windows system does it. I don’t know much about this and how imgui works with keyboard here, no idea if this can be handled