Kind of baffled by this one. Why can I style a layer in a web map and then have it look very different in the associated web app?
In the map below, the public facing web app completely ignores this shadow.
I've also experienced huge differences in the way that clustering is displayed. So much so, that I can't even preserve one of our maps that contained clustered points. I'm scratching my head trying to figure out why this is happening. I've even changed colors of symbols to make sure I'm editing the right layer.
What is the "web app" in this case? Do note that some apps (notably those built in Web App Builder) are still using the ArcGIS JS API 3.x, which lacks the advanced symbology options available in newer maps / apps.
Yup the more advanced symbols and labeling in Map Viewer are supported across other 4.x based apps (instant apps, dashboards, experience builder). They will get downgraded in Map Viewer Classic and other 3.x apps like WAB.