No Apps open. Just the browser. Firefox or Chrome. One Tab. Videoconferencing. Gather / Around / Skype / MSTeams / Gmeet / Jitsy all the same. The fans starts freaking out. And it’s loud OMG! CPU loads are at about 20-30%.
With video meetings it’s almost always happening at some point. Not right from the start but after some minutes.
Sometimes in usual work routines it happens as well. For example: Adobe XD / Skype / Trello / Firefox w/ 20 Tabs and some other Apps open. Happily designing away. Fan freaks out for minutes. CPU-load is under 40%
This is generally due to bad hardware acceleration!
The best solution is installing Throttlestop, a piece of software, and either disabling core turboing, or lowering the package power to something more along the lines of 15W!
Either way would reccomend looking into throttlestop! Pretty nifty piece of software.
It does not help that Skype and Zoom are hogs either. Surprised Jitsi is giving the OP issues though it is usually just a bandwidth hog, but with Firefox possibly without hardware acceleration well you might have that.