When projects get to a certain size and complexity, they can become difficult to manage. In this Unreal Tips & Tricks episode, we’ll look at an easy way to help keep the various elements in your project organized: custom thumbnails. Producing thumbnails for your projects and assets can make it easier when versioning, working in teams, and revisiting past projects. Let’s get started and explore the basics for tidying up files through visual mediums!
https://dev.epicgames.com/community/learning/tutorials/Kl0x/unreal-engine-how-to-create-custom-thumbnails