Five silent failures when automating real Chrome via CDP and how to fix them

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A developer running Chrome browser automation using raw Chrome DevTools Protocol (CDP) on a persistent user profile documented five failure modes that produce no exceptions or error messages. Key issues included Chrome silently blocking popups not tied to recognised user gestures, requiring the --disable-popup-blocking launch flag to resolve. OAuth flows caused further problems because some providers navigate the current tab rather than opening a popup, meaning code that only watches for new targets stalls indefinitely. On shared browsers with multiple tabs, automation risked attaching to the wrong OAuth target, requiring pre-click snapshots of target IDs and opener verification. Input events such as clicks and keystrokes were silently ignored when the target tab was in the background, fixed by explicitly calling Target.activateTarget and Page.bringToFront before each interaction.

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ProgrammingDEV Community ·

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