adding file from Project panel to Essential Graphics panel

I have several still images and logos in my project panels already. I'm sure I used to be able to just drag them across into the Essential Graphics panel to animate them. That does not seem to be possible anymore (unless I've missed something) in PP 24.1.0.

How can I get images/graphics/files from the project panel into essential graphics to avoid having to re-import them from scratch via the "From file..." option?