Attach the Chrome DevTools Protocol to a tab from an MV3 extension via chrome.debugger to run inspection/automation commands beyond content-script reach
domain: developer.chrome.com · 5 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Add "debugger" to the manifest's permissions array
Call chrome.debugger.attach({tabId}, requiredVersion), which resolves on success or rejects on failure
Issue protocol calls with chrome.debugger.sendCommand({tabId}, method, params), using method names from the Chrome DevTools Protocol reference (e.g. Runtime.evaluate)
Register chrome.debugger.onEvent to receive protocol events pushed from the target
Call chrome.debugger.detach({tabId}) when done
Known gotchas
Attaching shows the user a persistent 'extension is debugging this browser' info bar — it cannot be done invisibly
Only one debugger client (an extension or the DevTools window) can attach to a given tab at a time
CDP command and parameter names track the protocol version bundled with that Chrome release and can change between versions
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