What’s new in UI Toolkit?
UI Toolkit is a collection of features, resources, and tools for developing graphical user interfaces. First seen in 2019.1 as UI Elements, UI Toolkit introduced a retained mode UI framework that allowed for the development of custom UI for Unity Editor extensions. As of the 2021.2 version, UI Toolkit supports the authoring of runtime UI, so you can use it to create UI for games and applications directly in Unity.
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