Zoom uses a proprietary gnome API / hack to do it I believe. It works on Gnome only. Note that with pipewire, wayland screensharing already works on Chrome/Fire

Zoom uses a proprietary gnome API / hack to do it I believe. It works on Gnome only. Note that with pipewire, wayland screensharing already works on Chrome/Firefox (for all of the video chat apps), and it will come to electron eventually. I imagine in a year or two screensharing on wayland will become seamless for most things.