# stagehand-python@4.2.2a0.dev1605: fix : add new webmcp launch flag ( 3198)

Category: open-source
Published: 2026-10-15T20:25:01Z
Source: [Browserbase Stagehand releases](https://github.com/browserbase/stagehand/releases/tag/stagehand-python%404.2.2a0.dev1605)
Agent usefulness: 72/100
Confidence: 0.96
Content mode: release-watch
Verified: 2026-10-16T18:18:03.873Z
Tags: browserbase, browser-agent, automation

## Human Summary
Browserbase Stagehand releases published stagehand-python@4.2.2a0.dev1605: fix : add new webmcp launch flag ( 3198). why chromium versions newer than 157 require enable-features=WebMCP what changed added the new chrome flag to defaults Summary by cubic Adds the WebMCP flag to the default local Chrome launch flags across all SDKs so WebMCP works on Chromium…

## Agent Summary
Treat stagehand-python@4.2.2a0.dev1605: fix : add new webmcp launch flag ( 3198) as an official release signal. Inspect the linked changelog for compatibility and migration details, then run targeted tests before upgrading.

## Body
Browserbase Stagehand releases published stagehand-python@4.2.2a0.dev1605: fix : add new webmcp launch flag ( 3198). This automated release-watch entry was generated from the project's official GitHub release feed and is kept separate from human-reviewed editorial analysis. Release notes: why chromium versions newer than 157 require enable-features=WebMCP what changed added the new chrome flag to defaults Summary by cubic Adds the WebMCP flag to the default local Chrome launch flags across all SDKs so WebMCP works on Chromium versions newer than 157. Updates the WebMCP flag from --enable-features=WebMCPTesting,DevToolsWebMCPSupport to --enable-features=WebMCP,WebMCPTesting,DevToolsWebMCPSupport in TypeScript, Python, and Go SDKs. Updates docs and test fixtures to match the new flag. Written for commit c75f0d9 . Summary will update on new commits.

## Recommended actions
- Review the official Browserbase Stagehand releases release notes before upgrading.
- Check compatibility, migration, and security notes against your current agent stack.
- Run focused regression tests before production rollout.

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