As the one who started that particular thread I did rather wonder and even went back to the error and tried to imagine where it went wrong.
No way sneering, but I think this was self-inflicted. I have several times over the past years rushed to post where I didn't check thoroughly enough before doing that.
The extra print preview panel we have these days can add to the confusion. The cursor gets unwittingly moved all over the place. The capslock on my cheapo keyboard is liable to be tripped when typing "a" or more often using the left shift key.
It is easy to plonk the cursor in the wrong place or drag the text while trying to play with the words.
Sorry, I think this is just one of snags of two fingered typing by someone having a senior moment, I am a founder member of that club.