I tried importing jQuery into my Chrome extension, but when I try
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.0/jquery.min.js" type="text/javascript"></script>
It says that it Refused to load the script 'http://ajax.googleapis.com/ajax/libs/jquery/1.8.0/jquery.min.js' because it violates the following Content Security Policy directive: "script-src 'self' chrome-extension-resource:". What does that mean and, more importantly, how would I go about that?
Security reasons — extensions can do much more than a normal sandboxed web page. For that reason you’ll likely have to use a version of jQuery you package with your extension, instead of one to be loaded over the internet, especially one loaded over HTTP (vs HTTPS).