Mac's, PC's, OSX, Linux, Windows, I bet anything overheats when it touches "modern" conferencing technologies (which really is just WebRTC behind the scenes in many cases)... What is really curios is that even without video, thus just audio, it still gets hot...
Heck, even opening GMail or doing light browsing makes my laptop try to take-off from the desk (due to fans going full throttle)...
Who knows... Perhaps every site, sorry "web-app", is overtly doing crypto-mining behind the scenes... :) :)