Thanks for your answer,
I'm using the Q2A plugin: "WYSIWYG Editor v1.1.1".
Tried what you suggested, the problem stills happens. After I submit the answer or question, it looks fine it auto arranged to RTL, but in the editor the cursor is on the left side.
Looked into your link, but didn't provide any other solution, just people that reported on this bug.
Maybe the editor isn't updated? what version of CKEditor does Q2A provide?
And if it's not updated, how can I update it manually?