What's new in at-spi2-core 2.25.3:

* Fix -Wmisleading-indentation warnings.

* Fix memory leak of at-spi-bus-launcher.

* Add error-message, error-for, details, and details-for relation types.

* Poll direct dbus connections in the main loop--fixes processes
  being marked hung and the hung flag never being removed.

* Add Meson build system (thanks to Emmanuele Bassi).

* Various build fixes (thanks to Emmanuele Bassi).