isSaveAsAvailable(sLayer) {
			return Promise.all([
				Settings.getInstance(),
				Utils.getUShellService("Navigation")
			])
			.then(function(aPromises) {
				var oSettings = aPromises[0];
				var oCrossAppNav = aPromises[1];
				return (
					!oSettings.getIsContextBasedAdaptationEnabled()
					&& oSettings.getIsAppVariantSaveAsEnabled()
					&& sLayer === Layer.CUSTOMER
					&& oCrossAppNav !== undefined // Not a standalone app
				);
			})
			.catch(function() {
				// either Settings or ushell Navigation service from Unified Shell failed -> disable save as app variant
				return false;
			});
		}
Determines if Save As app variants feature is available in the connected backend.

@param {string} sLayer - Layer to check for key user app variants
@returns {Promise<boolean>} Promise resolving with a flag if Save As is available

@description App variant functionality is only supported in S/4HANA Cloud Platform & S/4HANA on Premise.
App variant functionality should be available if the following conditions are met:
When the current layer is 'CUSTOMER'.
When it is not a standalone app.
When the backend supports this feature.
@private
@ui5-restricted