I think perhaps the Visual Studio tooling is messed up in the latest version. I've successfully migrated an older pre-3.0 PCL XamForms app to a .NET Standard XamForms app and everything is working EXCEPT that app icon.
I get the default icon no matter what I do:
I've deleted and recreated the asset catalog several times, and it looks like the info.plist is correctly pointing to it because it can get my other images out of it inside the app.
It looks like info.plist points to Resources/AssetCatalog.xcassets/LaunchImages.launchimage under Resources, but the actually AssetCatalog isn't under the Resources folder.
If I close and reopen visual studio, then open the asset catalog, everything shows up in "Unknown" instead of it's correct place.
I'm not sure what to do to fix it.
WINDOWS MACHINE
Microsoft Visual Studio 2017 Version 15.7.3
VisualStudio.15.Release/15.7.3+27703.2026
Microsoft .NET Framework Version 4.7.03056
Xamarin 4.10.10.1 (f1760154c)
Xamarin Designer 4.12.1 (f3257e429)
Xamarin.Android SDK 8.3.3.2 (HEAD/dffc59120)
Xamarin.iOS and Xamarin.Mac SDK 11.12.0.4 (64fece5)
WINDOWS NUGET
.NET Standard Library 2.0.1
Newtonsoft JSON 11.0.2
sqlite-net-pcl 1.4.118
Xamarin Forms 3.0.0.561731
MAC MACHINE
XCode 9.4
Xamarin.iOS 11.12.0.4 (64fece54)
Windows and Mac fully updated, I've run Visual Studio and XCode and looked for updates on both, there are no other nuget updates on the Windows machine. I'm out of ideas to even TRY at this point, but I need to get this working ASAP!
EDIT
I can repro it on a BRAND NEW project. Just create a new XamForms project and add a image list to the Asset Catalog. Boom, you'll never have an app icon again. Uninstall / Reinstalling Visual Studio didn't help.