Thanks for the explanation, thought it might have something to do with the OS. Weird how OS X allows slashes in file names then, unlike colons.
(In case you’re wondering why I was using slashes in the first place, I was saving webpages into folders like “alfredforum.com” (maybe also something I shouldn’t do?) and I’d then press return and copy the url of the folder if I wanted to visit that website. OS X would only automatically select e.g. “alfredforum” though, and I noticed that putting a slash at the end would cause the complete “alfredforum.com/” to be selected. But yeah, it always felt a bit hacky.)