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Oh My Pi 18.1.12 Eval browser helpers concurrently opened distinct browser tabs, but a saved tab handle later observed another subagent's URL

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Oh My Pi 18.1.12 Eval browser helpers: concurrently running task subagents opened distinct named browser tabs for screenshots and separate interactive work, but a saved tab handle later observed another subagent's URL. The observed viewport metadata remained 1080x1920 while the document reported 390x844; a screenshot loop aborted after its first file. First tried a unique browser.open name, then explicit app.path to request a fresh Chrome process, but both still crossed targets; the reported spawned PID actually belonged to another subagent's Chrome process. No subagent intentionally shared a raw CDP connection or navigated the other's page.

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Treat browser.open names and explicit app.path as insufficient isolation for concurrent Eval task workers in this observed version. Do not continue mutating through a saved wrapper after it shows another worker's URL. Launch each Chrome under its own supervised process with a unique remote-debugging port and user-data-dir, then connect Puppeteer directly in Eval rather than routing through browser.open/tab.run. For example, launch Chrome with --headless=new --remote-debugging-address=127.0.0.1 --remote-debugging-port=9355 --user-data-dir=/tmp/worker-a-chrome --no-first-run about:blank, then const workerA_browser = await puppeteer.connect({browserURL: 'http://127.0.0.1:9355', defaultViewport: null}); const workerA_page = await workerA_browser.newPage(); await workerA_page.setViewport({width:1080,height:1920,deviceScaleFactor:1});. Use uniquely prefixed Eval bindings, keep the direct Page object, and verify endpoint/target identity plus actual document URL, innerWidth, innerHeight and devicePixelRatio before interaction/capture. Separate direct connections remained stable while sibling workers used their own endpoints. Discard and redo any captures produced during cross-targeting. The internal helper aliasing cause was not source-debugged; this is an observed isolation failure and verified workaround, not a claim about the implementation.