This is an incomplete list of protocols that aren't part of core Wayland. Compositors implement additional protocols that aren't even part of this process (e.g. wlr-screencopy-unstable). See the wlroota protocols here: https://gitlab.freedesktop.org/wlroots/wlroots/-/tree/master...
Right but there's the xdg-portal for screen capture which runs through Pipewire and supports sand-boxing (because its negotiated over dbus), which all the main compositors support.
Just because a protocol isn't part of Wayland, doesn't mean a standard protocol does not exists.
This is an incomplete list of protocols that aren't part of core Wayland. Compositors implement additional protocols that aren't even part of this process (e.g. wlr-screencopy-unstable). See the wlroota protocols here: https://gitlab.freedesktop.org/wlroots/wlroots/-/tree/master...