Browser agent cannot open after update 1.20.3

Google Antigravity
1

Description

After updating Antigravity to v1.20.3, clicking the browser agent button does nothing. No browser window opens, no log output, no error message — completely silent failure on Windows.

Additionally, when the AI agent tries to use browser_subagent / open_browser_url tool during a conversation, it returns:

local chrome mode is only supported on Linux

This worked correctly on previous versions.

Steps to Reproduce

  1. Update Antigravity extension to v1.20.3 on Windows
  2. Click the browser agent button in the UI → nothing happens (no window, no log, no error)
  3. Ask the AI to use browser_subagent in conversation → fails with “local chrome mode is only supported on Linux”

Expected Behavior

  • Clicking browser agent button should open a browser window
  • browser_subagent tool should work during conversations

Actual Behavior

  • UI: Clicking browser agent = zero response, no logs, no errors
  • Agent tool: open_browser_url fails with “local chrome mode is only supported on Linux”

Environment

  • OS: Windows 10/11 (x64)
  • Antigravity Version: 1.20.3
  • VS Code Version: Latest stable
  • Chrome: Installed
  • Previous working version: Pre-1.20.3

Impact

Browser agent is completely non-functional on Windows — both UI and agent-side.

2

I am facing the same problem, is there a workaround?

3

Same problem for me. Look like it is a same bug at 1.19 version.

4

I updated to 1.20.4 and now it’s working fine.

1 Like
5

Try updating to 1.20.4. It works well there

1 Like
6

Hi Everyone,

Thank you for flagging the issue. Please try updating the version 1.20.4 and let us know if still issue persists. Thanks @TDM_ER and @seaheachxv the community members for providing the fix.