Emm, it's not a text editor but showhtread.php?
Did you check that you have enabled allowing img mycodes in your account options? It's not related to script if it's working for other people. Check your account options: User Control Panel -> Edit options if you have selected "Display images in posts". If not MyBB postParser won't parse images correctly (they will be parsed, but not displayed).
Did you check that you have enabled allowing img mycodes in your account options? It's not related to script if it's working for other people. Check your account options: User Control Panel -> Edit options if you have selected "Display images in posts". If not MyBB postParser won't parse images correctly (they will be parsed, but not displayed).