When adding a link in the visual editor, the pop-up is either blank or a browser dialog interrupts and asks how to handle the "link.htm" file. In my case, this was caused by some htaccess mods associated with w3totalcache.
w3 total cache has some htaccess rules which may be optionally added to help with compression, caching, and headers. One of these lines is :
# BEGIN Define Mime Types (in case /etc/mime.types is poorly configured or incorrect) AddType text/htm .htm
Removing the second line solved the problem. Unsure of whether this was a bug/feature, or whether this htaccess line could still be helpful. Can anyone explain this further?
Similar to various other past problems previously solved by installing tinymce-advanced plugin ( http://wordpress.org/extend/plugins/tinymce-advanced/ ).
w3tcache w3 total cache
htaccess htm addtype
insert/edit insert edit link
"you have chosen to open"
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