In Chrome, IE and old versions of Firebug, spaces/tabs are allowed between "//# source[Mapping]URL=" and the URL (I assume this derives from the regex in
http://blog.getfirebug.com/2009/08/11/give-your-eval-a-name-with-sourceurl/ ). In Firefox, Firebug 2.0, and the spec ("Source Map Revision 3 Proposal") they are not.
Can we add support for this to the spec? While spaces there look slightly ugly, they are also harmless, and it would improve compatibility.