I tested this on two browsers and the results are: it works in Chromium, it doesn't work in Helium (both Chromium-based, Browser MCP extension v0.1.3 + server @browsermcp/mcp@0.1.3, macOS, accessed via npx opencode-browser).
Repro steps:
- Connect the Browser MCP extension to a tab and run navigate
- Run snapshot — works fine
- Run click or type (fill) on an element from the snapshot — fails
Actual behavior:
- In Chromium: all of the above work.
- In Helium: navigation and snapshotting work, but click and fill/type just return errors:
Error: No tab with given id 1995387775
(the id stays the same stale value no matter of which tab is connected)
Expected behavior:
The fill and click tools should work in Helium exactly as they do in Chromium, since both are Chromium-based.
I tested this on two browsers and the results are: it works in Chromium, it doesn't work in Helium (both Chromium-based, Browser MCP extension v0.1.3 + server @browsermcp/mcp@0.1.3, macOS, accessed via npx opencode-browser).
Repro steps:
Actual behavior:
Error: No tab with given id 1995387775
(the id stays the same stale value no matter of which tab is connected)
Expected behavior:
The fill and click tools should work in Helium exactly as they do in Chromium, since both are Chromium-based.