Font or contrast can make a difference for people having trouble to read due to eye problems of disorders like dyslexia.
I cannot tell anything about your case but you could try using accessibility settings in your browser to replace the default fonts entirely with specialized ones or just make it bigger.
As for your problem, it can be anything from natural ageing of your eyes to something far worth. Please keep an eye (no pun intended) on it and consider seeking medical help if your problem stays. Good luck!

you can easily change font for all webpages in firefox settings. can also use usercss just to be safe.

....I also make a ton more typos on Lemmy than elsewhere and I have no idea why. I thought it was an update to my phone's keyboard. Or my touch screen is misaligned or something.

I'm guessing there's more extreme errors than this example, but for "bat" and "car", "b" is two keys to the right from "c" and "t" is one letter to the right from "r", so that one seems plausible to typo.

I changed to the dyslexic font on a whim and I do kinda feel I read things better with it.

Someone else mentioned a browser add-on that lets you modify fonts on a per-site basis, but there are other add-ons in the same niche that don't require stylesheet knowledge if that puts you off at all.

As for errors, I'll sometimes not completely revise a sentence if I decide to rewrite for tense or aspect, and end up with words missing or in weird grammatical places. And then I'll not see it after three or four checks. Including when coming back to check whether people liked my comment or not.

And then bam, fifth visit, I can't parse what I've written because cabbage there's a wrong word in the middle of a sentence or I've one out entirely. (I did that for effect, but I can't vouch for the previous two paragraphs. Yet.)