New PHP Warning emitted in PHP 8 when a database rollback is attempted with no active transaction in MySQL

A new PHP Warning has been added to the MySQL database driver, which will be emitted when a transaction rollback is attempted when there is not active transaction:

trigger_error('Rollback attempted when there is no active transaction. This can cause data integrity issues.', E_USER_WARNING);

This will only happen in PHP 8 as earlier versions of PHP behaved differently (effectively failing silently) when commits / rollbacks were attempted without an active transaction.

If this log message starts to appear in your logs, you should review your code around database rollbacks as it may not be working as expected. If this is happening in core or contrib code, please report it in the appropriate issue queue.