tinymce plugin source code was not editable only in firefox
Tiymce was an html code editor
its having some plugins like font, color,code and etc
if user clicks on code plugin it will open a model with the html source code which user as created
that source code is editabe and working in other browsers
but in firefox its not editable
Hmm, on this demo, when I click View > Source Code, it is editable:
Does that one work for you?