[BUG] Claude Chrome extension Computer Tool crashes Chrome — debugger detach + GetAIPageContent flooding + ChildFrameCrash

Preflight Checklist

• [x] I have searched existing issues and while related issues exist (#25518, #30173), this report provides detailed crash forensics not yet captured
• [x] This is a single bug report
• [x] I am using the latest version of Claude Code

Environment

• macOS: 26.3.1 (Build 25D2128)
• Chrome: 146.0.7680.76
• Claude Chrome Extension: v1.0.61
• Claude Desktop: v1.1.6679
• Hardware: MacBook Pro M3 Pro, 18 GB RAM, Apple GPU
• Monitors: Single built-in display (also reproduces on multi-monitor setups)

What's Wrong?

Every time the Claude Chrome extension executes any task using the Computer Tool, Chrome crashes — all windows close simultaneously and must be reopened. This is 100% reproducible.

Detailed Crash Forensics

Chrome was launched with --enable-logging=stderr --log-file=/tmp/chrome-crash.log --v=1. The crash was reproduced and the full log analyzed. Here is the exact crash sequence:

Timeline (from verbose Chrome log)

18:33:22  Accessibility tree scanning (extension reading page DOM via ax_computed_node_data.cc)
18:33:30  ERROR: "Unchecked runtime.lastError: Debugger is not attached to the tab with id: 26529046"
          Source: chrome-extension://fcoeoabgfenejglbffodgkkbkcdhcgfn/sidepanel.html
18:33:30  [Computer Tool] Generated screenshot ID: ss_0415w2unr (905x758)
18:33:57  [Computer Tool] Generated screenshot ID: ss_7311zpzku (905x725)
18:33:59  GetAIPageContent SYNC burst — 4 renderers (PIDs 49033, 49108, 49100, 49128) scanned simultaneously
18:34:24  kBrowserWidgetMoved — Computer Tool repositioning the browser window
18:34:26  Navigation to chrome://new-tab-page/ — Computer Tool opened new tab
18:34:31  Display config update detected ("Displays updated, count: 1")
18:34:31  More GetAIPageContent SYNC calls across 3 renderers
          [log ends — ~1 minute gap before actual disconnect]
18:35:34  Chrome disconnected (confirmed by native host log)

Key Histograms at Shutdown

| Histogram | Value | Meaning |
|-----------|-------|---------|
| Stability.ChildFrameCrash.TabMarkedForReload | 0 | A child frame crashed, tab NOT marked for reload |
| Stability.ChildFrameCrash.Visibility | 2 | Crashed frame was not visible |
| GPU.GPUProcessTerminationStatus2 | 4 | GPU process failed (hw accel was disabled for testing) |
| DevTools.CDPCommandFromExtension | 14 | 14 CDP commands sent by Claude extension |
| Startup.CrashBubbleShown | 0 | Chrome showed crash recovery bubble |

Critical Observations

1. No crash dump generated — No new Crashpad dumps, no segfault reports in /Library/Logs/DiagnosticReports/, no SIGTERM/SIGSEGV in system logs. Chrome exits with code 0 (clean exit).
2. Debugger attachment fails — The extension logs "Debugger is not attached to the tab" but the Computer Tool continues operating anyway.
3. GetAIPageContent flooding — Multiple renderers are hit with synchronous page content extraction simultaneously, completing in microseconds.
4. The "Control Chrome" MCP server has never successfully executed a tool call — 34 unexpected disconnections logged over weeks, zero tools/call invocations ever processed.

Ruled-Out Causes

• Memory pressure: 64% free at idle, crash occurs even with minimal tabs
• Other extensions: Crash reproduces with all other extensions disabled
• External monitors: Crash reproduces on single built-in laptop display
• Figma / other heavy apps: Crash reproduces with no other apps running
• Hardware acceleration: Crash reproduces both with hw accel enabled and disabled

Related Issues

• #25518 — Debugger detaches on complex pages (closed/stale, same root cause)
• #30173 — Chrome crashed during UAT (open, less detail)
• #28517 — Extension crashes on javascript_tool/read_page (closed as duplicate)

Steps to Reproduce

1. Install Claude Chrome extension v1.0.61
2. Open any web page (tested with DoorDash, Gmail)
3. Open Claude side panel and ask it to perform any task that uses the Computer Tool
4. Chrome closes — all windows lost

What Should Happen?

Chrome should not crash. If the debugger attachment fails, the extension should handle the error gracefully rather than continuing to operate in a broken state.

Suggested Fix Areas

1. The extension should check debugger attachment status before sending CDP commands
2. GetAIPageContent calls should not be fired at multiple renderers simultaneously
3. The Computer Tool should abort gracefully if chrome.debugger.attach() fails, rather than proceeding with screenshots and page manipulation

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Diagnosed with Claude Code CLI via verbose Chrome logging, system crash report analysis, and native host log correlation.