The disorder’s called visual snow syndrome, it’s named after the main symptom that differentiates it from other disorders which is TV-static like visual distortion but it sometimes causes a lot of other things typically associated with migraine to the point before it was studied in its own right it was assumed to be an uncommon variation of migraine; unlike migraine though for many people it doesn’t produce any pain at all, just other migraine aura like neurological symptoms. I’m not so fortunate, I get a permanent one-sided headache, brain fog, occasional derealisation episodes, photophobia (that one’s fun but fortunately I live in usually grey Britain), and that general kind of thing. It was a migraine specialist researching the condition in the UK who eventually diagnosed which was good as at the time there was a fair bit of rubbish on the internet about the condition (though that’s a lot better than it used to be, I was sixteen when I got it and all the doctors could tell me at the time was ‘we have no idea what this is but it’s not going to kill you’).
As for treatments there basically isn’t one. Among other things I experimentally microdosed quetiapine against it (under the theory dopamine might be involved) under the supervision of a doctor which basically cured the visual distortion but not the pain, but I quickly built a tolerance and binned it off because the side effects aren’t great. Some people benefit from anti-seizure medications but not everyone and the side effects can also be bleak. Fortunately medical cannabis is legal in the UK and it’s very effective against the pain, the amount of unsuccessful things I’ve tried qualifies me for it and the pain’s only a problem on very bad days now. Coding with the monofur font helps me too!
Of course everyone has some noise in their visual system, a little bit of TV static isn’t necessarily indicative of disease. For reference I struggle to read when it’s bad, and my night vision is impaired quite a bit compared to what it was before so you’d definitely notice if it was problematic.