Squash of 3 work commits (Sep 2–6):
5c40761 cef: the build script downloads its CEF distribution itself, on every host, with no shell
eec516e cef: a Windows backend — the browser's page renders on Windows
3dce90e Propagate browser appearance changes to Chromium page media
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
54ea9be48a