Package: chromium Version: 57.0.2987.133-1 Wayland is the successor of X, and while many desktop environments (including Gnome), already switched to Wayland, Chromium still only runs on X, or in legacy mode on Wayland (using XWayland). However, it seems that Chromoium does support Wayland natively, but that it needs to be enabled on compile- and on run time: http://peter.sh/experiments/chromium-command-line-switches/
So I propose to build Chromium with Wayland support, and enable it when starting Chromium from inside Wayland.