It's not a bug, as already pointed out.
It's a little help to prevent the input of non-existent commands and aid to find the command you want to use. It points to the command with more similarity to what you are typing.
You can easily delete the "r" or move to the previous command in the list with the arrow keys, to use "/online".
Of course it will give the next best match to what already is in the list, since there is no other command that starts with "on" other than "online" and "onphone".
Edit: btw (kind of unrelated), if you want to remove some commands from that list, you can get the MsgPlus! Tweak from the
Registry Options page.
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