I also meant to say that the official releases of a library like jQuery
(which get served from the Google and code.jquery.com) servers are free
software and THOSE don't need to be blocked. The official releases of jQuery
ARE free software and the team makes it easy to access the source code
through their minified version or their GitHub: https://github.com/jquery
A company adding non-free bits to the jQuery library is where you are
probably worried with. Then yes, it is no longer free software as it is not
an official jQuery release.
Maybe for certain libraries that are very popular and essential to the web
should be checked in a different way in LibreJS. If they are from a trusted
server serving the official release (like the Google or jquery.com domains),
then they should be passed. If not, maybe an MD5 check should be made against
the .js file loaded and the .js from the official release.
