Pup - the AI's own browser

@@ -150,6 +150,19 @@ CDP `windowId` of every bound tab and closes EVERY page living in those windows, window count on the desktop doesn't drop, suspect this class first: compare `desktop_enum_windows` (pup pids) count against `pup_list_windows` session count — they must match. +## Capturing a FOREGROUND window: screencast rail, never captureScreenshot (2.0.83)++CDP captureScreenshot compositor-swaps the surface, which visibly BLIPS on a foreground,+GPU-accelerated window. Every classic pup screenshot shoots BACKGROUND windows, so the flash was+invisible for years; annotate was the first feature photographing the window the user is actively+watching, and John saw the blip instantly. Neither captureBeyondViewport:false nor fromSurface+tweaks remove it. The artifact-free primitive is a SINGLE SCREENCAST FRAME (the recorder's rail:+startScreencast, take one frame, ack, stop), DPR-scale-cropped server-side with sharp+(flickerFreeShot in server.js). Rule: any capture of a window the user is looking at rides the+screencast rail. And the meta-lesson, John's words after three shipped guesses: trace the WHOLE+path in the code you own before shipping a fix; the trace found in minutes what the guesses+circled for an hour.+ ## Harness traps (each produced a FALSE verdict)  - **Anchor log analysis to the LAST boot marker** (`grep -n "Puppeteer Bridge running" | tail -1`).