I'm not sure if this has already been posted but here's a chat bug for you that I guess happens when you paste a link that has an apostrophe in it (like many Card Hunter items have). For example this is what you copy: http://wiki.cardhuntria.com/wiki/Items/Bewlin's_Baffling_Bauble This is what you get when you paste in chat: http://wiki.cardhuntria.com/wiki/Items/Bewlin%27s_Baffling_Bauble NOTE: the link looks correct in chat but the actual link has that mysterious 25 added to it.
"%25" is the urlencoded value for "%", so it's likely that the link is being urlencoded twice, somehow.
Still extant. Web/Flash client, Flash 22.0.0.209, Chrome 52.0.2743.116 m. Steps to repro: 1. Paste the following link including a URI-escaped apostrophe (as per OP) http://wiki.cardhuntria.com/wiki/Items/Quinn's_Buckler 2. Click link created in chat 3. Link leads to http://wiki.cardhuntria.com/wiki/Items/Quinn%27s_Buckler Bug: New link has incorrect escaping.