When you have a youtube video embedded in a post and you try to edit that post, the video appears over the top of the dialog making it unusable.
Ah, I've found some more information on the problem, and it turns out there is a parameter you can add to the end of the youtube embed URL that fixes it. (?wmode=transparent)
Would maybe automatically addding it to the embed code be a possibility?
Here's some more info on the issue: http://www.jenkaufman.com/youtube-iframe-embed-video-problem-hides-menus-other-layers-546/
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