What we know
"Quake in Your Browser". An npm package says its WebQuake-based engine powers netquake.io, and WebQuake is an HTML5 WebGL port of Quake by Triang3l. We could not read the site's own about text or find who runs it.
Links
Source and tools
Coverage
Deep dive in progress
This page is a short entry. The full write-up (original game, who built the port, how to play, creators and sources) comes next.
We have not confirmed whether it needs your own game files. The engine is open source. Not legal advice. Never run a launcher or download from a page you do not trust.