title: Migrate User Under Existing Firebase Auth Provider to Another
body: <p>I created an app where users could sign-up through Facebook. However, I want to delete it altogether and replace it with just a Google sign-up. </p>
  
  <p>For existing users, who signed up via Facebook only and have already accrued backend data in Firestore, is there any way I can manually add the "password" or "google.com" auth provider so the existing account remains untouched and the user can use as is after the fact I delete Facebook's login SDK?</p>
  
  <p>Would these users have to create a new account with a new email address and start over. Or, would I need to keep Facebook's login SDK and corresponding account linkage code.</p>
  
  <p>This is for less than 10 users. Any help would be appreciated.</p>