Web what? – How native gaming is coming to browsers

Blog posts in the form of "Here are the technologies making it possible to bring modern native gaming to the web" have been around for a long time, and that's probably the sort of thing they're referring to.

One that comes to mind as particularly memorable is the asm.js Citadel demo (some info here: https://blog.mozilla.org/en/mozilla/mozilla-and-epic-preview...), although there was a similar one a year earlier about UE3 (https://blog.mozilla.org/en/products/firefox/mozilla-is-unlo...).

In 2015, Unity 5 was released with WebGL support. Engine support for having the Web as a target certainly led to a lot of excitement among gamers at the time too.