Google Fonts is a library of 1462 open source font families. It's used by many websites and applications - including WHMCS - to display high-quality and appealing fonts consistently across different devices, platforms and Operating Systems. The fonts are hosted and maintained by Google, eliminating the need to maintain your own font repository.
An issue has been identified in the 8.6.1 release - published on 3rd November 2022, that causes an issue with email sending when using the Google Mail Provider. Email sending fails with the following error:
Class "WHMCS\Module\Mail\SmtpOauth" not found in /path/to/whmcs/modules/mail/SmtpMail/SmtpMail.php
We have opened case MODULE-7874 to investigate this error further.
Once we resolve cases and push features they are available at our change log, here:
I apologize for the inconvenience, and appreciate your patience as we work to resolve this.