I would strongly suggest serving this landing page via http/2.0 - your 504 requests over http/1.1 are currently taking 3.5 minutes for me to load 2MB of data.
https://gist.github.com/4lejandrito/6d4f903e0a692b87344e8600...
The resize function only resizes the first time and uses a cached version of the image after that.
I checked the server and the CPU is not too high so I think it must be HTTP as parent pointed out.
Ignore my comments, then.
Using 500 requests for this because http2 exists is like stating it's ok electron apps eat 1 Go of ram because we have big configs today.
That's also why, in 2019, with quad cores, SSD and more memory than ever, things doesn't feel faster than 10 years ago.
For now I am just disabling the background samples so that only 1 creepyface is loaded per user. Should be ready in a few minutes.
For testing it in the browser: in Chrome at least, the developer tools Network tab details the protocol of each request/response. I believe Firefox has similar functionality.