Microsoft Teams Costum Layout

How to I access "Costum Layout" in Microsoft Teams?

Several articles from 2020 said "it would come out later this year" (see below), but I cannot find any possible accesspoint to it in Micrsoft Teams on my Mac.

I am Using MAC OS, my version of Microsoft Teams is 1.4.00.4971. It was last updated on 10/05/2021.

I would appreciate any help. 

https://techcommunity.microsoft.com/t5/microsoft-teams-blog/what-s-new-in-microsoft-teams-microsoft-ignite-2020/ba-p/1665600?OCID=usoc_TWITTER_MicrosoftTeams_M365_spl100001541463943

https://mspoweruser.com/microsoft-teams-breakout-rooms-custom-layouts/