You should never select Firefox if you get an "Open with" download dialog. That will never work, oth

You should never select Firefox if you get an "Open with" download dialog. That will never work, otherwise Firefox wouldn't ask. If you ticked to do that automatically then you need to reset that action or you end up with Firefox opening endless windows or tabs.

See "Reset Download Actions": http://kb.mozillazine.org/File_types_and_download_actions

A possible workaround is to use this extension:

Open in Browser: https://addons.mozilla.org/firefox/addon/8207