[BUG] Browser pane computer{action:"left_click"} dispatches clicks at the wrong coordinates (2.5x-4x off), silently missing the target
Preflight Checklist
- [x] I have searched existing issues and this hasn't been reported yet
- [x] This is a single bug report (please file separate reports for different bugs)
- [x] I am using the latest version of Claude Code
What's Wrong?
In the Browser pane, computer{action:"left_click"} — whether given an element ref or a raw coordinate — dispatches the real click event at the wrong screen position, off by a large and inconsistent multiplier (~2.5x–4x in my repro). The tool reports success at the requested coordinate, but the actual trusted click event the page receives lands elsewhere — in my case, entirely below the visible viewport, hitting <html> instead of the intended element. No error or warning is surfaced; the tool call just "succeeds" while the intended UI action silently never happens.
What Should Happen?
A left_click at coordinate (x, y) — or at a ref's resolved position — should dispatch a real click event whose clientX/clientY match that position (within normal rendering tolerance), landing on the intended element.
Error Messages/Logs
None. This is the core problem — there is no error signal. I only detected it by installing a capturing listener on the page:
window.__clickLog = [];
window.addEventListener('click', function(e) {
window.__clickLog.push({ clientX: e.clientX, clientY: e.clientY, target: e.target.tagName, isTrusted: e.isTrusted });
}, true);
Measured results:
<html>
<body>
<!--StartFragment-->
Click type | Requested (CSS px) | Actual clientX/clientY | Ratio | event.target
-- | -- | -- | -- | --
ref-based | (138, 435) | (353, 1113) | ≈2.56x | HTML
raw coordinate | (138, 435) | (565, 1781) | ≈4.09x | HTML
<!--EndFragment-->
</body>
</html>
Error Messages/Logs
Steps to Reproduce
Open any page in the Browser pane; resize to 1280x720 via resize_window.
In the page, install the capturing click listener above.
Pick a known interactive element; confirm its real position via getBoundingClientRect() (mine: x:12, y:425.67, w:232.67, h:18 → center ~(138, 435)).
Call computer{action:"left_click", ref:"<its ref>"} (or coordinate:[138,435]).
Read back window.__clickLog via javascript_tool — the intended UI action (e.g. opening a tab) does not occur, and the logged coordinates don't match what was requested.
Claude Model
_No response_
Is this a regression?
I don't know
Last Working Version
Unknown / not tested.
Claude Code Version
Unknown from this environment — please fill in from claude --version.
Platform
Anthropic API
Operating System
Windows
Terminal/Shell
Other
Additional Information
Windows 11 Pro (build 10.0.26100), Browser pane (mcp__Claude_Browser__* tools) driving a local Vite dev server.