3.2.2: Understanding change of context

Hi,

I have read and re-read SC 3.2.2 however I am still confused on
understanding 'change of context'. I am writing to get
further clarification.

The definition of changes of context
<https://www.w3.org/WAI/WCAG21/Understanding/on-input.html#dfn-changes-of-context>
states
'moving focus to a different component' is one of the examples of change of
context.
Does that mean opening a modal window is a change of context?
If yes then how do we comply with 3.2.2 (informing the user ahead of time)?

Typically when the modal window is opened the focus is set to the modal
itself.
Upon checking accessible modal examples by W3C
<https://www.w3.org/TR/wai-aria-practices-1.1/examples/dialog-modal/dialog.html>
no
information is relayed to the User about 'opening the modal'.

Pardon me if this has been discussed earlier and I would appreciate it if
anyone can share additional reading material on this subject.


Thanks,
Kalpeshkumar Jain