Firstly, does the Firefox Accounts page say that the email was sent, or does it prevent you from sending? It's normal for it to suggest a different email domain when using a non-standard email address, but I don't think it actually blocks you from sending it.

If it's actually being sent, have you checked your junk/spam folder? Certain email providers have strict filters, so perhaps the email is being blocked entirely. You can try adding the accounts@firefox.com to your address book/contacts, since this normally makes it a trusted email for your account.

Also, you'll want to disable any automated replies or vacation notifications, since the Firefox Account system usually treats those as errors.

Hope this helps.

See also:

• https://support.mozilla.org/en-US/kb/forum-response-firefox-sync-verification-email-faq

In case of issues try to login to the Firefox Account via this website.

• https://accounts.firefox.com/signin
• https://accounts.firefox.com/settings

cor-el said

See also:

• https://support.mozilla.org/en-US/kb/forum-response-firefox-sync-verification-email-faq

In case of issues try to login to the Firefox Account via this website.

• https://accounts.firefox.com/signin
• https://accounts.firefox.com/settings

Thanks a lot. I did get a dialoag saying that mail was sent, and I did check my spam folder before writing my question (should have noted that in the question - sorry). The https://accounts.firefox.com/signin doesn't require the confirmation e-mail and I could sign in - however I now see that my browser still doesn't consider me to be signed in. So - question isn't really solved after all.

Also I can't set up 2FA, account recovery as my e-mail has never been verified. I think changing the e-mail might be the only solution. But it works fine for 188 other sites :-D

Did you try adding the accounts@firefox.com email address to your contacts on your email account? It could be that your email provider is filtering out emails from that address. Typically, adding the account to your contacts will mark emails from that address as "trusted" and they shouldn't get blocked.

Wesley Branton said

Did you try adding the accounts@firefox.com email address to your contacts on your email account? It could be that your email provider is filtering out emails from that address. Typically, adding the account to your contacts will mark emails from that address as "trusted" and they shouldn't get blocked.

Thanks for the suggestion. Unfortunately it doesn't help. I've added accounts@firefox.com to my contacts and signing in to Firefox Sync again. Still no e-mail gets send. Hoping some sysadmin of Firefox could look into some log-files to find out what is really happening here.

Changed my e-mail and solved the issue. Any Firefox website developer reading this should consider looking into this issue. I'm finished wasting time on this website bug. Still love FireFox browser.