I get a lot of lag in Krita, and it was said in a video that if you disable OpenGL,the lag goes away. After doing that, it started glitching weirdly every time I zoomed in.
Yes, this is why we have openGL enabled by default, because this is literally why we implemented the openGL canvas to begin with. Turning off OpenGL is only meant as a last resort, if updating your graphics drivers doesn't help. I am going to close this, as it is as fixed as we can make this.