Change volume on all users at the same time

Hello, on my old pc, i had a adjustment bar in the top right corner that let me adjust the volume of all users in teamspeak at once, is this a plugin/addon or is it something in settings?
thanks for the reply!

Make a right click next to Help and enable the Toolbar and the Master volume.
Or open Settings and change volume of playback there. It’s the same slider.


thank you so much!