Zend certified PHP/Magento developer

Convince macOS and FireFox that I speak English

On macOS and FireFox I have always installed everything in an English locale and set everything I can find to English, yet the browser and OS both frequently seem to change languages at random times to the language of my VPN IP. Can I fix this?

Here’s what’s been checked / set thusfar:

  1. Apple menu > “System Preferences” > “Language & Region” (Shows English only and Region = United States)
  2. No other languages set as “Application languages” on the OS
  3. No “translation languages” downloaded on the OS
  4. In FireFox: Menu > Settings > Language is set to English. “Set Alternatives…” shows Deutsch as the 2nd choice behind English and it won’t let me remove it.
  5. browser.translation.detectLanguage is set to False
  6. browser.translations.enable is set to False
  7. intl.locale.requested had US-en, de. I removed de.
  8. intl.multilingual.aboutWelcome.languageMismatchEnabled is set to False
  9. services.sync.prefs.sync.intl.accept_languages is set to False