Serviio

I am using Serviio with Roku Ultra LT and want to use a different icon. I found some old posts at viewtopic.php?f=3&t=4942 suggesting replacing png and jpg files in the jar file to get this result. However, it seems this is not working with the latest version anymore. I made changes, stopped the service, replaced the jar file, and restarted the PC, but the icon didn't change. Please advise how to change the icon and what resolution of the new icon is required/recommended. Thank you.

Those posts are more than ten years old. Serviio has been updated a dozen times (or more) since then. I do know that the Serviio icon has changed in that time as well. It's possible that it can't be altered anymore, but I can't say for certain.