Reviewed PR #1651 (standard-risk / medium) for the Clips native recorder fallback path. The patch is directionally solid: it blocks the ScreenCaptureKit→screencapture fallback for clear macOS Screen Recording permission denials, keeps the fallback output path on the active backend, and adds immediate output validation plus focused unit coverage for the new matcher and file checks.

The main architectural concern is error propagation rather than the fallback detection itself. The new verify_screencapture_output() helper now produces actionable permission-oriented failures, but one of those failures is still masked later in the stop/save pipeline, so the PR does not fully eliminate the generic missing-file error it set out to replace. Aside from that, the approach is sound and the tests are appropriately scoped to the touched logic.

Key finding:

• 🟡 MEDIUM: actionable screencapture validation errors can still be replaced by the old generic missing-file failure in save/upload flows.

🧪 Browser testing: Skipped — PR only modifies backend/config/docs, no UI impact.