We noticed a behaviour/bug in MapImageLayer Sublayer rendering.
We have some polygons with relatively complex symbology:
When we set an opacity to that layer, and at the same have a popupTemplate setup, then when we click on the map, it "downgrades" the symbology to a simple fill (and it stays downgraded until you reload the app).
Simple code taken out of the API sandbox:
If I don't set any opacity, then it works fine. If I don't set any popup it works fine too, although It seems to me the issue is linked to the opacity (?).
Interesting. I'm not sure what's occurring here, but I need a better test case to diagnose. Is that service that you're using public? I need to find a hosted MapServer that has complex polygon symbology (because if I define a complex renderer on a polygon, it may not be the same test).