So I reviewed the pastebin you sent me and there isn't a specific reason why you should be having issues with posting in extra releases. If you go into your settings, make sure you're not using the Enhanced editor. It causes a lot of problems on chrome and may be causing your issues. You can find this under "General settings" under My Account.
(http://imgur.com/LOODVVt)
I always use Opera but i tried to rewrite the whole thread and it didnt work. Tried on Chrome and there it worked. Seems to be a problem with Opera then.
When i try to post in this thread I get the same error from a week ago.Yesteday i successfully written a post in this thread,but when try to edit it or add new post i get same error." Error code 15 This request was blocked by the security rules"