I'm having very different behaviors with nested contenteditable="false" elements within a parent contenteditable="true:
<pre> <div contenteditable="true"> <span>I'm supposed to be editable</span> <p contenteditable="false">I'm NOT supposed to be editable.<br>Neither should I.</p> <span contenteditable="false">I'm NOT supposed to be editable.</span> </div> </pre>This fiddle exemplifies how two elements that should not be editable are in fact editable with Inteet Explorer 11 but not Google Chrome. What gives?
I have seen some people applying a strange workaround by setting them to "true", which indeed works for IE, but has the opposite effect on Google Chrome (as it should).