• Certain javascript sites may not display correctly
• Sites that use ActiveX will not work
• The 'ebrary reader' plugin does not work
• Factiva (formerly Dow Jones Interactive) has display issues
• Some formatting done in cascading style sheets does not display correctly
• Forms may not work as expected
• The Mr. Sid plugin does not work (display of .sid files in Insight and the DL)
• World Biographical Index: When you click a language, it opens a new window with the frames for searching, but if you click a search type, it fails to load the search form.
• Insight's Browser Version does not work
• The Virtual Reference Client (Ask!Live) on the librarian side does not work.
• China Database Online does not work with Firefox

Firefox enables 'pop-up blocking' by default. Some applications including the browser version of Insight and the Finding Aids application will not work correctly with this enabled.

Firefox does allow you to selectively enable pop-ups on specific URL's, to do this for the Finding Aids:

"This is done under: Tools -> Options -> Web Features. Simply click "Add" and add the URL (either the DNS name or the IP address) of the site you want to enable. In this case you can add: "webtext.library.yale.edu" Leave "Block Popup Windows" checked."
(Note: Thanks to Brian Kupiec, Beinecke Systems Officer, for this tip.