For local development on our Macs we use MAMP Pro, which uses the port 8888 for sites. Since upgrading to Firefox 14, if we enter the URL of a local site into Firefox, it removes the custom port we've added and returns a 403 error. Chrome and Safari work without issue as they don't delete the port. For example, if I browse to http://my.test.site.localhost:8888 which up until version 14 worked fine, Firefox removes the :8888 and instead tries to load http://my.test.site.localhost, which fails. If I browse direct to an inner page like http://my.test.site.localhost:8888/page1 it works and the port stays. But it won't work to the root URL. This is causing major issues for us. It's not a banned port - why is Firefox ignoring the port we enter?