You’re probably going to end up on Jitsi meet, but I’m also going to drop a recommendation for bigbluebutton.

I recently noticed that it was integrated into the open source Learning-Management-System Canvas, which every school I have gone to so far uses.

Although bigbluebutton doesn’t seem to explicitly support e2ee (but maybe this counts for something), if you are already using Canvas, BigBlueButton definitely worth looking at.

I really, really wish people at my school would use the integrated bigbluebutton instead of using zoom, especially given I’ve seen people occasionally have issues with authentication for zoom, but all of that stuff is handled with bigbluebutton because it’s fully browser based and integrated into Canvas.

https://www.zoomeye.hk

Similar site as shodan, but different company. I’d recommend checking there as well.