Episode images are not recognized by all platforms, podcast websites, players or devices. There are several screenshots below showing what the same episode looks like within each instance, the platform or app name is listed in RED for each.

Episode images must be at least 1400×1400 to be recognized by Apple so this has become the industry standard. 

The below screenshots were taken on 1/14/20 and may be subject to change based on each individual service and when they do software updates.