AT-SPI2 defines 3 coordinate types: SCREEN, WINDOW, and PARENT. Ref: https://gitlab.gnome.org/GNOME/at-spi2-core/-/blob/main/atspi/atspi-constants.h#L126

The SCREEN coordinate type works reliably. When using WINDOW and PARENT coordinates, the size is often wrong. The coordinate type really shouldn't affect the width and height at all.

This can be easily tested by selecting an accessible object in Accerciser and requesting extents in each coordinate space:

In [25]: acc.get_extents(0).height

Out[26]: 512

In [26]: acc.get_extents(1).height

Out[27]: 1342

In [27]: acc.get_extents(2).height

Out[28]: 1342

This also affects the object:bounds-changed notification which returns results in window-space.

Related: https://gitlab.gnome.org/GNOME/at-spi2-core/-/issues/72