Open the Display Editor for the popup you want to edit.

Select "Image & Background".

Click either "Change Image" or "Edit Image".

Change Image: Select either the Unsplash or Upload tab, then click the image you want to use from the list.

Edit Image: The editor will open — make your edits and save.

Adjust the focal point of the display. The selected focal point is indicated by a blue dot with a white outline.