Editing photo in timeline

So I’m trying to crop an image I put into the timeline. When I select the image and go into filters and add the crop then edit the size of the crop nothing happens. I have the video at the moment I want to crop it at and nothing is happening. This works fine with a normal video but does it not work with still images? And if that’s true that’s dumb and they should change that.

Crop’s working fine with an image.