Info
Firebase js SDK version:
Issue description
firebase.auth().confirmPasswordReset() is throwing the wrong error. Instead of auth/user-disabled, it throws auth/invalid-action-code.
Steps to reproduce:
  1. Create an email-password user.
  2. Disable user.
  3. Send password reset email to user.
  4. Attempt to reset password using oobCode

In Firefox 70.0.1, this error is thown:

 { code: "auth/invalid-action-code", message: "The action code is invalid. This can happen if the code is malformed, expired, or has already been used.", stack: "" }

instead of this more relevant error that is thrown in Chrome 78.0.3904.108: 

{ code: "auth/user-disabled", message: "The user account has been disabled by an administrator." }
The latter error is more relevant because the action code is valid, current, and unused, the problem is that the user is disabled and it would be nice if this was reflected in the error message.

Auth info

Firebase sign-in status: Unknown
Firebase auth currentUser object value: 
null

Firebase Email & Password Authentication

Step 1: Create user
Result:
Step 2: Disable user

This will call a cloud function to disable the user since it cannot be done client side.
This can also be done from the firebase console.

Result:
Step 3: Send password reset email

This will send an email to the user with a link to reset their password.
This can also be done from the firebase console.
Click on the link in the email and then copy the oobCode for the next step.

Result:
Step 4: Reset password using oobCode

This will attempt to reset the user's password to "querty123" using the provided oobCode.
This is the part that is throwing different errors on different browsers.

Result: