Currently it's not possible to remove Object Style by styles combo, when you select an marked style item in the list, the style will just get re-applied.
(try to remove the image-left-align on the demo: http://ckeditor.com/demo#full)
there's a ticket
http://dev.ckeditor.com/ticket/5336
stating this is fixed, but it's not for me, (4.1 (revision 80c139aa)) neither for the demo.
Is this a regression?
I think that #5336 was closed
I think that #5336 was closed before this issue was spotted on Chrome. Anyway, there's a ticket for Webkits: http://dev.ckeditor.com/ticket/10065 and AFAIR there was no way to fix it easily.
Piotrek (Reinmar) Koszuliński
CKEditor JavaScript Developer
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