Within an xLights session, if you bounce between layouts the preview cache does not cleanup. It grows to include previews of old and the newest layouts. After bouncing a couple times the Preview list can grow to become large, and with duplicate values.
A short video demonstrating this issue is shared here: https://youtu.be/C9ZdEsKEIC0
I believe the desired result is for the preview to only show the relevant groups of the currently loaded layout?
Thanks.