Claude Desktop 1.1.6041: Renderer process causes extreme CPU usage (~60%) on macOS Tahoe 26.2

Environment

• Device: Mac mini (Mac16,10) — Apple M4 / 16GB
• macOS: Tahoe 26.2 beta (Build 25C56)
• Claude Desktop: 1.1.6041 (updated 2026-03-10)
• Claude Code CLI: 2.1.72

Problem

After Claude Desktop auto-updated to 1.1.6041 on March 10, the app causes sustained high CPU usage even with only one window open and minimal interaction. This was not happening before the update.

Observed CPU Usage

| Process | CPU% | Notes |
|---------|------|-------|
| Claude Helper (Renderer) | 60.7% | Single window, idle |
| WindowServer | 45.7% | Pulled high by Claude's GPU compositing |
| Claude Helper (GPU) | 13–22% | |
| Claude (main) | 5–6.6% | |
| kernel_task | 9.5% | Thermal throttling kicks in |

Total Claude Desktop footprint: ~80–100% CPU across its processes.

Impact

• Mac mini M4 (normally cool and silent) becomes noticeably hot
• kernel_task engages thermal throttling → system-wide UI lag
• WindowServer GPU Time accumulates to 3:51+ within ~25 minutes of uptime
• Load average: 1.95 / 2.75 / 3.41 on a 10-thread chip

Reproduction

1. Launch Claude Desktop 1.1.6041 on macOS Tahoe 26.2 beta
2. Open one conversation window
3. Observe Activity Monitor — Renderer process sustains 30–60% CPU without user interaction

Timeline

• Before March 10: Mac mini stayed cool even with Claude Desktop open for hours
• March 10 ~20:35: Claude Desktop auto-updated to 1.1.6041
• March 10 onward: Persistent high CPU and heat

Workaround

Quitting Claude Desktop (Cmd+Q) immediately resolves the issue. Claude Code CLI is unaffected and works normally.

Hypothesis

Likely a rendering loop or GPU compositing issue in the Electron renderer, possibly triggered by a compatibility problem with macOS Tahoe 26.2 beta's WindowServer.