According to http://www.w3.org/html/wg/html5/#contenteditable if an element has contentEditable=false then it should not be editable, even if the rest of the document has designMode='on'. This testcase proves that Firefox, Safari and Opera fail to disable the editing in such situation. Filed in Mozilla as https://bugzilla.mozilla.org/show_bug.cgi?id=462735
Created attachment 24842 [details] testcase The second paragraph shouldn't be editable
*** Bug 58966 has been marked as a duplicate of this bug. ***
I think this bug should have been fixed since http://trac.webkit.org/changeset/85267.
Confirmed that the bug no longer reproduces on the latest nightly build. *** This bug has been marked as a duplicate of bug 53031 ***