Firebase Phone authentication on Web not working with Firebase custom domain

[Rajesh Mani]

Hi,

I am using Firebase phone authentication on Web and when I login via custom domain https://<domainName> I am taken to the phone login screen.

However, when I enter the phone number and press submit, I get an error around not being able to send SMS.

Chrome Console log of the error

"...recaptcha sign in succeeded

www.googleapis.com/identitytoolkit/v3/relyingparty/sendVerificationCode?key=AIzaSyCov2Dmr9TVXcVISKaY-uhfCqIwypgnFBE:1 POST https://www.googleapis.com/identitytoolkit/v3/relyingparty/sendVerificationCode?key=AIzaSyCov2Dmr9TVXcVISKaY-uhfCqIwypgnFBE 400 ()

SignupPage.js:341 [SignupPage:VerifyPhone] Error on sending verification code! ..."

The issue doesn't occur when I use the <projectName>.firebaseapp.com that the custom domain is associated with.

Looking for some guidance on if there is any known issue with phone authentication on custom domain or if any tweak needs to be done to the Firebase phone authentication for it to work with custom domain.

Thanks in advance

[Bassam]

Hey Rajesh, did you add your custom domain to the list of authorized domains in the Firebase Console -> Authentication -> Authorized Domains section?

If not, then the issue is related to that.

Best regards,

Bassam

[Rajesh Mani]

Yes that fixed the error - I didn't realize there was this step required. Thanks Bassam. 

Rajesh