Instrument redraw sources, per-output request coalescing, and animation fallback scheduling. Route local visual changes to their affected outputs while preserving deferred grab and gesture updates.
Schedule fallback recovery using each orphaned animation output's refresh interval, suppress it while a normal frame chain exists, and retain requested final frames after scheduling failures. Add mixed-refresh, cursor footprint, frame-chain, and disconnect regressions and document measurement limits.
Cancel callback-only timers when a frame is submitted and defer callback delivery until retirement. Cover a delayed timer and missed presentation deadline in the scheduler tests.
Clean up shader argument borrows and shell region decoding to pass Clippy.
Samuel Onoja