Package: libglfw3 Version: 3.3.2-1 In the currently packaged version of libglfw3, there is a bug that causes for inputs to be delayed or ignored in the X11 session (and also Wayland via Xwayland) which causes a frustrating experience in affected games. This issue is fixed in this commit: https://github.com/glfw/glfw/commit/9a3664b4a992a5a9b669179098542b0f882dece7, but Debian does not package the fixed version (3.3.3 and newer).
I suggest that the issue is fixed by updating libglfw3 to version 3.3.3 or newer. It would also be possible to fix the issue by patching the current version with the commit referred to above. I am using Ubuntu 21.10, kernel 5.13.0-23-generic, and libc6 2.34-0ubuntu3.