<<THIS REPOSITORY IS DEPRECATED>> The HTTP Archive provides information about website performance such as # of HTTP requests, use of gzip, and amount of JavaScript. This information is recorded over time revealing trends in how the Internet is performing. Built using Open Source software, the code and data are available to everyone allowing researchers large and small to work from a common base.
https://github.com/HTTPArchive/legacy.httparchive.org/blob/master/custom_metrics/wpt_bodies.js
It seems that name attribute values are case sensitive, so this line will only get a subset of meta descriptions.
target.total = [...d.querySelectorAll('head meta[name="description"]')].map(e => {
The line should be:
target.total = [...d.querySelectorAll('head meta[name="description"i]')].map(e => {
Same goes for the selectors in the calculateAllRobots function.