No I did not realize that, it would seem however that if my OS or browser did the checking, that the check would be the same here as in say Google, which may also have it's own check. So what is going on, is nevertheless wrong, but it may be less clear than it seems. However I have never seen words that I clearly spelled incorrectly, change their spelling automatically, in real time, before I even begin the next word, before using this site. At other times, the software, from wherever it comes, merely underlines a word which is telling me of an issue, that only I can resolve, as often tenses of the word are involved.
In fact I just opened a new link on Google, and this issue does not happen there at all. If I can turn this off in IE, and someone knows how, please let me know.