with the new SDK 2.2.3 you can build for Fenix 5.
In the deveoper blog the resolution and the icon size was presented.
Icon size is alway 40x40.
After compiling for 5S i get this error:
BUILD: ERROR: The specified icon is larger (40x40) than the allowed icon size (36x36) for fenix5s
The both other Fenix5 are working.
Maybe there is a mistake in the presented discription or in the SDK?