List of functions/keywords specific to Percona MySQL 8.x

I have a commercial web application that requires Percona Server for MySQL 8.x only. They don't support MySQL/MariaDB and even have code to check for these databases and abort the application. But I don't believe that they use any functions/features specific to Percona Server that make them incompatible with the stock MySQL/MariaDB. I checked the source code and there are no Percona-specific encryption functions , UUID_VX functions , data masking functions and no PERCONA_SEQUENCE_TABLE . I have disabled the check, and the application now runs in a testing environment with the stock Debian mariadb-server 10.11.11-0+deb12u1 without issues (yet). Is there anything else that can cause compatibility issues? EDIT: I'll repeat the title of the question: I'm looking for a list of functions and keywords specific to Percona MySQL 8.x so I can grep the source code. MariaDB compatibility is out of scope. I have already identified a possible scenario. Their previous versions supported MariaDB (our installation has been running on stock MariaDB/MySQL included in Debian for more than a decade). In the recent version, they added JSON fields but this feature wasn't supported by older MariaDB versions included in Debian before Bookworm so they went with a simple solution and wrote down into the requirements that they support the only database they have locally - Percona. But this is just my assumption and I need exact proof that their requirement to run the app with Percona has no basis, so I can push through the dismissive support to the developers. UPDATE: I managed to get to the developers and they confirmed what I suspected: "We officially support only Percona 8 = Because it is the DB we use in the cloud and test on it. Unofficially I can say that we work with MySql 8.0 without any problems.". I also managed to get them to describe some specific issues they encountered with MariaDB and they all are caused by the use of JSON type fields. They refuse to fix these issues on the ground that "JSON is not inherently included in the basic SQL standard, but it is part of the SQL:2016 standard (ISO/IEC 9075:2016), which MariaDB does not support.". After being told that JSON fields are not part of the standard, they stopped communicating.