Yes, Teams uses a function that is unsupported by Xwayland (XGetImage, if I remember the backtrace correctly), so it crashes. I worked around it with a rather convoluted setup that involves running Xephyr under Xwayland, then running Teams under Xephyr (via setting `DISPLAY`), and running vncviewer under Xephyr connected to a VNC server (wayvnc) sharing my screen on the parent wayland instance. Then I tell Teams to share the "whole screen" (ie the entire Xephyr window) and quickly maximize the vncviewer window (within the Xephyr window).

To be able to maximize vncviewer you do need a compositor running under Xephyr too. I picked i3 to be the most minimal. Again, i3 can be told to run in the Xephyr window by setting `DISPLAY`.

One caveat is that I still use Teams under Wayland to join calls for the audio, so this setup means I need two Teams instances to join the same call. This works for meetings but not for individual calls. Of course if you want to use the Xephyr'd Teams to do audio too there shouldn't be any problem; I just prefer having easy access to the Teams window to mute myself, etc instead of having to reach into the Xephyr window and unmaximize the vncviewer window.

People on the #sway IRC channel on Freenode suggested an alternative might be to use v4l2loopback to create a "camera" device that is sourced from the screen and then have Teams use it as a webcam, but I couldn't get v4l2 to work on my distro (it kept insisting my distro's ffmpeg couldn't encode video even though it could) so I didn't investigate further.