I was able to fix the issue by doing the following.
* Deleting the /uploads/js-cache/ folder (it’ll be recreated)
* Clearing browser cache
* Logging out, logging out
I also modified the domain name in the settings to have only lowercase letters in it, as opposed to ProperNoun.com I switched to propernoun.com. Not sure if that had an effect on it.
Previous to this I was having the white screen problem after hitting “insert into post” in 2.6.3 randomly. I was getting errors in FF that included permission denied to “location.to_string” and “Window.send_to_editor”. Presumably that was a result of something gone wrong in the tinymce javascript cache.
