My intuition is that it is a hardware failure. GPUs can develop issues that show up intermittently. You can try running GPU stress-testing software to check if that’s the case.

However, did you recently update your graphics drivers? If you did, try rolling back to an older version.

I do. I proofread everything to make sure that swipe typing got it right, and I judge people who get it wrong.

It does bug me that the possessive form (fundamental to the language) rather than the informal contraction is the non-standard one, but I suppose it matches “his” and “hers”.

I have no problem communicating with people through verbal means, but I don’t get body language beyond the obvious (e.g. smiling). I mean, I get why people do it but I don’t get how people do it. Generally this isn’t a big deal but it does make dating really frustrating. I can communicate my own interest indirectly through verbal innuendo, but if the other person is doing anything non-verbal then I’ll miss it.

Yeah, and there’s no meaningful difference between terms “substance” and “matter” except that “matter” is probably the one that the test taker is expected to memorize without really understanding.