This patch should work for the time being (until PHP 9 is released a few years from now), though it would be infinitely better to refactor the code to use the libxml_set_external_entity_loader() function instead. Unfortunately, I don't feel I have enough of the domain specific knowledge needed to be in a good place to create that particular patch, so I will need to leave that future iteration to you or others in the GetID3 team.
As discussed via email.
This patch should work for the time being (until PHP 9 is released a few years from now), though it would be infinitely better to refactor the code to use the libxml_set_external_entity_loader() function instead. Unfortunately, I don't feel I have enough of the domain specific knowledge needed to be in a good place to create that particular patch, so I will need to leave that future iteration to you or others in the GetID3 team.