Thanks, that did the trick (obviously it will).
Anyway, I tested it a bit further. It happens only when I use advanced editor, i.e. I don't use quick reply. If I use quick reply, there's no action in moderators' log. But with advanced editor (using buttons
Reply to thread (I removed java script ID, so first click on buttons
Reply to thread goes directly to advanced editor) or going to quick reply and then choosing advanced editor) it logs it.
Please, try posting with advanced editor and see if your posts get logged.