Wifi Uses CA Certificate in .cer Format
Our school has a secure wifi network that requires we log in. While we can use it without importing a CA cert, that's insecure and probably even against the rules for security reasons. We're provided two CA files in .cer format. Technically Linux is unsupported and these are directions for Mac OSX. But they work closely enough up to the point where network-manager refuses to import a .cer file.