[ooboe]

In the Jitsi thread (https://news.ycombinator.com/item?id=22758131) also currently on the front page, someone from Jitsi mentions that they do have a way around this and that they don't decode the video on the server:

"We use a technique called simulcast. It consists on making every participant "work a bit harder" for the good of the bunch.

That is, every participant sends 3 separate video resolutions to the server: 720p, 480p and 180p (this may change due to bandwidth constraints). Then the server will only forward the approopriate layer to each other participant. So, if you are only seeing me in a thumbnail it will only forward the 180p layer. If I become the active speaker (or you choose to pin me to the large view) the server will immediately switch to forwarding the 720p layer."

So s/All/Not all/. Note that Jitsi does not claim to have e2e encryption.