I don’t think this is a major issue, but lately I’ve noticed the live spellcheck and auto-correct are doing something a bit weird.
If I type a word like naive or decor that are sometimes used (appropriately) with an accent but leave the accent off when I type it (lazy!), the auto-correct feature will automatically change it to the accented version. And then the live spellcheck will flag it as an error. When I right click it, the spellcheck will recommend the unaccented version. If I change it back to the original, no more red flag.
I’m on the latest version, with English (United States) as the language. All spelling options are checked except for “ignore words with numbers”.