Have you tried clearing your cache, or restarting your browser?
Chrome sometimes acts weird.Try clearing cache and relogin.
Try with Firefox to know whether it is browser issue .
sometimes if some other moderator approves the posts and you try to approve being on application since long then this 'loading..." message gets displayed, you may confirm this as well.
I see that you have created a private support case for this issue. Support will continue investigating this issue specific to your site in your case.