I can confirm that CSS is sent gzip'd, but no matter what I try for JS, it does not get compressed. I tried working around it by prepending a PHP script, but the content-type remains text/html even if I send a header stating otherwise.
The <FilesMatch> .htaccess directive appears to void auto_prepend_file, but setting Expires works for JS files using <FilesMatch>. Now I'm out of ideas. I've Googled and searched these forums specifically, but I still couldn't find a definitive answer.
Has someone experienced this issue before, and has anyone successfully fixed it? Thanks.