me too, clean mIRC, no scripts.
In your example, it looks like this is happening with the single character channel name "#". I am not sure how this relates to the PREFIX/CHANTYPES combination issue you were reporting on IRCnet due to duplicate prefixes.
The behaviour in your last post is intentional for hotlinks due to the fact that, if it wasn't, all single character punctuation marks would be treated as channels, which makes no sense when parsing text. There are no plans to change this behaviour.
