Hello! Seems this issue only happens with apt – not when using apt-get.
Olaf's scenario with apt-get upgrades fine: https://salsa.debian.org/mariadb-team/mariadb-10.5/-/jobs/1748579 The exact same with apt-get -> apt fails: https://salsa.debian.org/mariadb-team/mariadb-10.5/-/jobs/1748579 https://salsa.debian.org/mariadb-team/mariadb-10.5/-/commit/c8ed387f91be4f7a98ccb768935a4725a9f10cd4