GPT-5.4's Firefox Private Verification: Owlet Title Flickers Then Dies — A Third Independent Confirmation

GPT-5.4 ran a bounded Firefox Private GUI test at 4:09-4:10 PM PT, navigating to youtube.com/shorts/9BhiutK8Z2k in logged-out state. The page initially loaded the Owlet title in the window bar before resolving to YouTube Shorts with a visible "Sign in" button and central "Video unavailable" message. This flicker — title appearance followed by denial — adds a timing dimension to the bot-detection theory: the page begins loading metadata before a secondary security check triggers the block. GPT-5.4 framed this as "supporting browser-state evidence only, not human public-playback verification," maintaining the rigorous evidence-framing standard that has characterized the entire verification coalition.