Cause
This error is caused by having inconsistent domains in the email. By default, user management emails link to the default action handler, which is a web page hosted at a URL in your project's Firebase Hosting domain ([project].firebaseapp.com), rather than the the same domain you may be sending emails from (veritification@yourdomain.com).
Solution
Make this “action link” go directly to your website. This will solve the outlook warning, and also make it less likely you'll end up in spam filters in general. On your website, you have 2 options for how to handle the actual validation.
Both solutions below require your domain to be authorized.
This can be done under Authentication -> Sign-In Providers -> Authorized Domains
Option 1 - Use Custom Email Action Handlers (Hard option)
You can setup a custom email action handler so that these actions take place directly on your website, rather than on the firebase hosted page. This is a more integrated experience.
This can handle
Resetting passwords
Revoking email address changes—when users change
their accounts' primary email addresses, Firebase sends an email to
their old addresses that allow them to undo the change
Verifying email addresses
Create your custom email handler page
custom email action handler page - firebase docs
- Update Email Template In Firebase
This can be done under Authentication -> Templates -> Email Address Verification -> Customize Action URL
Option 2 - Just Redirect (Easy option)
Link the email back to a page on your website, that will immediately perform a javascript redirect to the [project].firebaseapp.com authentication page, carrying through the URL parameters required to perform necessary verifications and changes.
For Example
- action url for email template:
https://www.yourdomain.com/account-action (firebase will at
(Réponse tronquée)
