Why the fuck does autocorrect randomly capitalize certain words? It's so irritating. I've never had any issue with commas though, so I don't know where that's coming from.
If they have their keyboard set to a different language but type in English anyway, then it learns English words exactly how they're spelled. Which means they probably spelled Window with capital W at some point and then it got autocorrected to that exact spelling.
Oh, I see. That makes total sense. Mobile keyboards have truly wrecked the general population's ability to use proper grammar. One thing I've noticed a lot is that they also tend to insert unwanted apostrophes. For example, typing "its" always corrects to "it's," which is very frustrating.
Sometimes your keyboard also remembers when exactly you use certain words - like in the beginning of sentences, which most keyboards will capitalize by default.
I hate the whole "its" being converted to "it's" no matter what thing, but what I hate more is when I teach the keyboard a word, and it STILL won't let me use it. Taught my keyboard "that'd" and it would autocorrect it to "that's" every time. And unlike other words, if I went back and manually corrected it back, it wouldn't leave it, it'd force it back to "that's" again and refuse to let me change it. Come to think of it, it did that with "it'd" to "it's" too. Eventually I just switched to a different keyboard with much less aggressive autocorrect, since I still need the autocorrect to type with any semblance of speed due to minor coordination issues.
My old keyboard abruptly started autocorrecting more typos into what I was saying than it corrected toward the end anyway. Probably some shoddy attempt to implement AI auto correction.
Google's keyboard is the absolute worst for that, tried using it for a bit but I'm back to SwiftKey which isn't absolutely insane (and which has more customization options too)
I still miss Swype too, and hopefully one of the open source keyboard apps will get good enough to replace all of them soon enough
I'm on SwiftKey too and switched from Gboard for similar reasons. The only reason I'm not running one of the open source ones is that typing with one hand is unbearable without being able to to swipe, and I use my phone in bed a fair bit.
That, or if they're like me, the person is just very tired. If I am extremely tired, I basically just hit shift on every word and don't care about it. In such cases, I might fix my posts and comments in the morning, or even delete them if they feel too much like "what the fuck did I write there".
Another key to identify those is double words.
Example: I Only Started Started Using Computers When When I Was 14.
It might come from languages like German where nouns are capitalized. Even in English proper nouns are capitalized so I don't see why that bothers you so much