How do I show my preview window?

Im following some beginner tutorials and one of the things they reference is the preview window inside of the inspector. I dont have a preview window there at all and can’t seem to figure out how to make it show up. Could someone help a newbie out?

Select an object in the Hiearchy that can be previewed (Image, model 3D, …) At the very bottom of the inspector, there is a button with the name of the selected object and two horizontal lines. Just click on it

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