How to prevent CKEDITOR from adding image dimensions as a style?
Instead of this:
Similar to Cedric Dugas' solution, there is a patch to a ticket for CKEditor here that helped me a lot solving this problem :
http://dev.ckeditor.com/attachment/ticket/5024/5024_6.patch
I used it but trimmed the code a little bit so that just images are processed by the filter. This solution works when the image gets inserted but also when it is resized with the handles in the editor.
Hope it helps