Looking at the pre-compressed content config here …

https://httpd.apache.org/docs/2.4/mod/mod_deflate.html#precompressed

So the idea is to create gzip versions of your css, js, etc. and Apache will recognize their existence and send the gzip version instead?

So we can have both whatever.css and whatever.css.gzip in the directory and Apache with this config will know to grab whatever.css.gzip if it exists?

What exactly is this doing?

# Serve correct content types, and prevent mod_deflate double gzip.
    RewriteRule "\.css\.gz$" "-" [T=text/css,E=no-gzip:1]
    RewriteRule "\.js\.gz$" "-" [T=text/javascript,E=no-gzip:1]
Thanks