overly glitchy screen when typing out a post

[IkuStudies]

its maybe not a big deal to others, but the glitches were enough for me to say ok enough is enough, i'm trying to think and look at what I'm typing and its flying all over the screen. I'm using a firefox browser on a linux, and i just did an experimental post and as i typed the input screen was glitching everywhere, no idea how to fix it but i thought i would submit it as an observation, great job everybody:)