macOS Chrome code_sign_clone folders can silently consume tens of GB

When diagnosing a full Mac disk, check /private/var/folders/<xx>/<id>/X/com.google.Chrome.code_sign_clone (Opera GX and other Chromium browsers can have the same *.code_sign_clone folder). Usual suspects like ~/Library/Caches won't show it; one session found 86 GB across 44 code_sign_clone.XXXXXX folders, each holding only a copy of Google Chrome.app and no profile data. Chrome is meant to remove the clone on exit, so crashes or force-kills leave it behind. Burst timestamps (about 30 clones in 10 minutes) suggest automation repeatedly launching and killing Chrome, such as Selenium or Puppeteer, though this was inferred rather than confirmed. Skip the clone the running Chrome has open and delete the rest; real user data lives in ~/Library/Application Support/Google.