This avoids some issues which could happen on some setups[0] due to
meta-native-renderer.c:dummy_power_save_page_flip →
meta_onscreen_native_swap_drm_fb implicitly turning of the primary
plane (by destroying the KMS framebuffer assigned to it):
* drmModeObjectSetProperty could return an "Invalid argument" error
between setting a non-empty cursor with drmModeSetCursor(2) and
enabling the primary plane again:
Failed to DPMS: Failed to set connector 69 property 2: Invalid argument
(This was harmless other than the error message, as we always re-set
a mode on the CRTC after setting the DPMS property to on, which
enables the primary plane and implicitly sets the DRM property to on)
* drmModeSetCursor(2) could return an "Invalid argument" error between
setting the DPMS property to on and enabling the primary plane again:
Failed to set hardware cursor (drmModeSetCursor failed: Invalid argument), using OpenGL from now on
[0] E.g. with the amdgpu DC display code.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1240
2e5b767c01