Input lag only when using switch pro controller with celeste through steam

[rbits0]

When I am using the switch pro controller through steam, there is a lot of input delay/weirdness in Celeste. There is delay, and some joystick inputs don't go through etc. I am using Celeste from itch.io btw (OpenGL). This happens wired and wireless. When steam is not open, there is no input delay. The weird thing is though, it is only with the pro controller and celeste. If I use my PS3 controller, no lag, and I also haven't noticed any lag in any other games. It seems to only be the combination of Celeste, Steam, and the pro controller. I have also tested another pro controller, and it has the same problem.