With the 2 new templates called EB (stands for Episode Banner) and EBN (stands for Episode Banner Navigation), it is easy to put the episode banner on infobox episode without showing the banner file name, also applying those templates can remove the params |previous2
and |next2
from the infobox episode.
Below is an example.
{{Infobox episode | banner = {{EB|2}} | image1 = Candy Factory Map.png | image2 = Candy Factory Map Mobile.png | image3 = Episode2background.jpg | previous = {{EBN|1}} | next = {{EBN|3}} }}
You will get: