Fix Guide: Tahoe Safari "Service Worker" High CPU

Symptom: Safari on macOS Tahoe causes high CPU usage even when all tabs are closed. Activity Monitor shows com.apple.WebKit.Networking using 100%+ CPU.

Why this happens

Legacy service workers from sites like YouTube or Slack can get stuck in an infinite update loop within Tahoe's new Safari sandbox.

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Fix 1: Clear Safari Service Workers

1. Open Terminal.
2. Run the following command to purge the worker cache:

rm -rf ~/Library/Containers/com.apple.Safari/Data/Library/Caches/com.apple.WebKit.Networking/ServiceWorkerCache

1. Force-quit Safari and relaunch.

Fix 2: Reset Safari Networking

1. In Terminal:

killall com.apple.WebKit.Networking

Recommended Tool: 1Password

To reduce the number of active background extensions and workers:

- Get 1Password for a highly optimized extension that doesn't trigger the WebKit networking loops common with legacy password managers.