Browserbase has launched Stagehand v4, which moves target management, state and CDP dispatch into a browser extension that runs next to the page, the company said on 10 August 2026.
Browserbase said the change means remote browsers now behave like Chrome running on a laptop. Previous automation frameworks keep a local copy of browser state, which can drift out of date when the browser is in another region and cause errors.
In Stagehand v3, domain policy was enforced from the client, so a pop-up opened by the page could start loading before the policy reached it. In v4, target management and enforcement run inside the browser.
The same architecture lets Browserbase offer TypeScript, Python and Go SDKs at feature parity. The company said moving the core into the browser also made WebMCP support and real clipboard interaction possible.
Stagehand is Browserbase’s open-source framework for AI browser automation.