Last commit, 2016. Last issue, 2018. Open issues in 2014 "verify compatibility with {KDE,Gnome,etc}" and no comments. :(<p>It's so so so frustrating the current state of Wayland fragmentation. X11 wasn't secure, but at least it worked.
I have little idea how this works in practice, but absolutely super in love with the idea of having security policy for describing different capabilities upon a desktop. Wayland made things secure, and this is trying to figure out how we make them share-able.