Yes it is an invalid character but clicking on the link in the original post demonstrates that perhaps it should be the browser that filters it out instead of mIRC. No browser I used specifically rejected the URL.
I'll reiterate that people should post their URL's accurately instead of blaming mIRC for it. Given that there are valid characters either side of the > means that mIRC would then have to work harder to process the link the way you want it to. I also dispute your claim that posting URLs in a chatroom with < and > added is common. Just because one sees something alot doesn't make it common. I am yet to see any link posted this way in 6 years of IRC. Infact the only place I have seen this is in a link to an attachment in old versions of Microsoft Outlook.
