Otherwise it falls back to full damage. If we still want to do partial damage in those cases, we'd probably need some kind of accumulated damage history for each buffer.
Bug 1656533 Comment 0 Edit History
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Otherwise it falls back to full damage. If we still want to do partial damage in those cases, we'd probably need some kind of accumulated damage history for each buffer. See also https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/316#note_279673