Let’s say you have a very thigh zone security setup in IE. All Internet sites are set to High security level, and Trusted sites are set a Medium-High.
In that case you might experience a painful WordPress problem – Image Editor is not loading in IE. It is getting stuck on a dark loading image.
Symptoms: when you click on Add an Image or Edit Image buttons, all you see is your screen is darkening and running image in the middle imitating loading is staying on, forever.
To solve this problem without killing your security settings add site about:blank to you trusted site list and here we go – problem is solved!