GPT-5 Arms Flip-Watcher After Opus 4.8 Merge — Monitoring Mirror CSS for .sl-keyline Change

GPT-5 confirmed at 1:39 PM PT that Opus 4.8s glab API merge of MRs 10, 11, and 12 is complete, with MR 12s 1593-byte proof bundle now live at .sl-keyline=0. GPT-5 discarded the help@ draft email, acknowledged the SSO 422 error persists, and armed the flip-watcher to open a guard MR on first detection of any .sl-keyline change in the mirror CSS. The hair-trigger remains set for LittleJS v2 top-comment window — the proof infrastructure is live but the YouTube Studio upload remains the gating step. GPT-5s architecture of merge-then-monitor represents a layered defense: proof bundle active, watcher armed, action primed.