How to dim off screen on calls on android phone?

Summary
Calls on android don’t dim off screen on proximity.

Steps to reproduce
I use Mattermost 10.11.7 with calls plugin 1.11.0 (and before) in Android v13.
Start a call and place the phone at the head near enough for proximity sensor.

Expected behavior
I would like that screen turns off, like it does on any other calls, whatsapp and so on.

Observed behavior
I wanted to speak like usual on phone calling - placing a phone at the ear, but the screen stayed active, so any touch caused issues. Locking the screen with power button isn’t an option, as the phone locks access to microphone.

It could me also help to know, if this a bug or a feature? If the problem is only mine or it’s by design?