Microsoft announced a new suitability to give specific users the ability to test new “public features” within the Teams desktop (Windows, MacOS & Linux) and supported browser clients before they will rolled out world wide.
“Public Preview for Microsoft Teams provides early access to unreleased features in Teams. Previews allow you to explore and test upcoming features. We also welcome feedback on any feature in public previews. Public preview is enabled each Teams user, so you don’t need to worry about affecting your entire organization.