Comment 63 for bug 1753776

(In reply to Daniel van Vugt from comment #16)
> d) Add a small feature to mutter to allow the caller (gdm3) to specify
> that only simple (linear?) formats are allowed, so as to enable easy
> transitions for all display server types. gdm3 probably cares less about the
> benefits of compression than gnome-shell-proper does.

It should be enough to exclude any modifier for which gbm_device_get_format_modifier_plane_count() returns > 1. I don't have any plans to do this in Mutter, I can look at the long-term getfb2 solution.