It would be nice if you could click them to launch a web browser instead of copy/pasting stuff.
*** Bug 5296 has been marked as a duplicate of this bug. ***
Fixed by the move to reStructuredText/Sphinx in bug 4951.
I could not reproduce the original issue using the built in PDF reader in Google Chrome and the TAG from 4.13.0. I guess google does some magic to recognize URLs on its own.
I could however reproduce the issue with the 4.13.0 TAG using evince, and can verify that it's now fixed in the TAG from the latest jenkins build.