[BUG] Claude in Chrome extension causes repeated Chrome crashes on macOS Sequoia + Apple Silicon (M2 Pro)

Bug Description

The Claude in Chrome extension causes Chrome to repeatedly crash/renderer to die on macOS Sequoia with Apple Silicon. The extension works briefly after a fresh reinstall + Claude Desktop restart, then crashes again within minutes during normal use. This is not limited to split view mode — it happens during regular browsing with the side panel open.

Steps to Reproduce

1. Install Claude in Chrome extension on macOS Sequoia (Apple Silicon)
2. Open Claude Desktop app
3. Click the Claude extension icon in Chrome to open the side panel
4. Use the extension normally for a few minutes
5. Chrome renderer crashes — either the tab dies or the entire browser closes

What I've Tried (None of These Fix It Permanently)

• Uninstalling and reinstalling the Chrome extension
• Quitting and restarting Claude Desktop app (this temporarily fixes it but crashes return within minutes)
• Running claude --chrome-native-host to restart the native messaging bridge
• Removing other browser extensions (removed "Do Browser" AI agent extension)
• Reducing open tabs to 9

Observed Behavior

• After reinstall + Desktop restart: extension works for a few minutes
• Then crashes again — either renderer process dies or full Chrome crash
• macOS diagnostic report shows Chrome exceeding disk write limits (8.6 GB in 13.5 hours), suggesting the extension or native host bridge may be causing excessive I/O
• The native host sometimes runs on a stale Claude Code version (2.1.49) while CLI is on 2.1.50, suggesting version sync issues between Desktop and the bridge

Expected Behavior

The extension should work reliably without crashing Chrome.

Environment

• macOS: 26.0 (Build 25A354) — Sequoia
• Hardware: MacBook Pro (Mac14,9), Apple M2 Pro, 10 cores, 16 GB RAM
• Chrome: 145.0.7632.76
• Claude Code CLI: 2.1.50
• Claude Desktop: Latest (installed via DMG)
• Architecture: arm64 (Apple Silicon)

Related Issues

This appears to be the same underlying problem reported in multiple closed/ignored issues:

• #16201 — Closed as "not planned" (split view crash, EXC_BREAKPOINT)
• #21890 — Closed as duplicate of #16201 (renderer crashes correlated with extension)
• #26305 — Desktop app connection failure
• #24935 — "Not connected" despite correct setup
• #24593 — Extension persistently fails to connect
• #27073 — MCP tools fail silently

The root cause has been attributed to Chromium bug #355266358 (sidePanel API crash on macOS ARM), but no workaround has been shipped by Anthropic despite this affecting users for 2+ months. At minimum, the extension should detect the vulnerable environment and fall back to a popup UI or tab-based interface instead of using the broken sidePanel API.

Suggested Fix

Implement a fallback when sidePanel is unstable:

// Detect vulnerable environment and fall back to popup/tab
const isMacARM = navigator.userAgent.includes('Mac') && navigator.userAgent.includes('ARM');
if (isMacARM && isSequoiaOrLater()) {
  // Use popup or tab instead of sidePanel
  chrome.tabs.create({ url: 'claude-panel.html' });
} else {
  chrome.sidePanel.open({ windowId: window.id });
}

This is a paid product feature that has been broken on Apple Silicon Macs for 2 months. Please prioritize a workaround rather than waiting on an upstream Chromium fix.