Of course Waylands protocol support server-side buffers. The question is how compatible it would be with the rest of the environments when everyone expects client-side buffers.
First, that assumes Mir will be done before Wayland has implemented the missing parts Canonical needs. This is far from certain.
Even if it was true, that is why Wayland supports extensions. Canonical could have written their own extensions for Wayland that did things quickly and dirty, then ported away from them (or not) when Wayland devs got better implementations in the official protocol. No fork would have been needed, just extensions.[/QUOTE]
Mir probably will. It's developed in a much higher peace than Wayland. But I'm also thinking about the future when both are "done"
and Canonical says next Ubuntu version will have THIS and starts developing it with four months to go.
And there you have it again. A possible break in compatibility in Ubuntuís Wayland compared to everyone elseís.
It's better for everyone to have two display servers than one that is incompatible with other builds of itself.