Finfo Moved Away From Resource
Finfo functions have moved from resource to objects. In PHP 8.1, instead of returning a resource, it now returns a finfo object. Checks based on is_resource() must be upgraded, and are now dead code.
PHP code
<?php
var_dump(finfo_open());
?>
Before
resource(4) of type (file_info)
After
object(finfo)#1 (0) {
}
PHP version change
This behavior changed in 8.1.