2.3.5 The “Ok” button and its main distinctions from the “Cancel”
The “Ok” button closes the properties menu window and sets
up as default the values of parameters for the subsequently created objects
thus invoking the “Apply” button functional, but does not change
the properties of the currently selected objects in the model.
The majority of the new TS versions are not available on this button,
Tekla Structures v21.1
Tekla Structures v2021
The “Ok” button is most common for the older TS versions where
it executes the very functional described above.