On my site, I’m using Apache’s ‘mod_deflate’ and ‘mod_filter’ to compress my compressible responses (mostly text), with a setup based on h5bp’s server config. I got my sites running over HTTPS recently, and today, when looking at my site performance with webpagetest.org, I noticed that my content wasn’t compressing. It was still working fine over HTTP. I noticed in h5bp’s comments that <IfModule mod_filter.c> could be removed in Apache versions below 2.3.x. I removed it, and sure enough, compression was working again. I’m not sure why it’s different depending on what protocol I use. Perhaps Dreamhost has separate versions of Apache running for the two protocols. Or perhaps it’s just something different about the configuration in the virtual hosts. Regardless, it’s working now. I just hope this doesn’t cause problems whenever they move to Apache 2.4.