CI: add Debian Bullseye (and assorted fixes to make it pass)
Bullseye isn't that old so for the benefit's of Xwayland let's make sure we build on it.
See xorg/xserver!975 (comment 1825835)
cc @ofourdan
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Bullseye isn't that old so for the benefit's of Xwayland let's make sure we build on it.
See xorg/xserver!975 (comment 1825835)
cc @ofourdan