Certificates not working in Android phone


I have installed a trial CA certificate into my Android 6 and Android 8 Samsung phones, but when I accessed the website, it said my trial CA certificate was not safe.

I try to install the same trial CA certificate into iPhone and Window, it is working, no warning pop up, and the trial CA certificate is valid.

Does anyone know why the trial CA certificate is not working on Android phones?


This may allow the CA to work.

  • install the CA to the OS
  • Open firefox and go to the settings
  • Select About Firefox
  • Tap on the logo till you get a message that the debug menu is enabled
  • Go back to the main settings page
  • Select Secret settings
  • Enable Use third party CA certificates (may require force stopping Firefox or a reboot, swipe closing is not enough)