Issue: Can't edit a certain comment

Hi, I started having a problem with my comment 2 days ago and today I'm no longer able to edit the comment. I can start quick editing the comment but when I click to 'Save' or 'Go Advanced' the page starts to load and loads a long time. When the loading stops I get a white empty page only and nothing gets saved in the end. I'm left at page http://aarinfantasy.com/forum/editpo...postid=4356989

I'm able to edit and save my other comments just fine.

I cleared my aarin related cookies once so far but it didn't help. I haven't tried deleting all my browser history because there are important things that I can't delete just yet.
I was wondering if it's a problem with my browser (Firefox) but I tried the same with Google Chrome and the problem is the same. I cannot edit and save that comment.