Is AVIF image support available when using PHP-GD in PHP 8.1?
At this time, this is not supported in the libraries that cPanel offers through EasyApache. There is an open feature request here that you can vote and comment on if this is a feature you would like to see added:
Our feature request site is actively reviewed and curated by our development team to identify potential future build plans and to accept ideas and suggestions from our community. Voting on this feature will increase the chances that the feature will be added to the cPanel software.