Example of Protocol, File Extension, Alias, definition in AppxManifest.xml

ProtocolFileExtensionAliasManifest.xml

<Extensions>
        <uap:Extension Category="windows.fileTypeAssociation">
          <uap:FileTypeAssociation Name="wpfmsix">
            <uap:SupportedFileTypes>
              <uap:FileType>.zip</uap:FileType>
            </uap:SupportedFileTypes>
            <uap:DisplayName>WPF MSIX Detect</uap:DisplayName>
            <uap:Logo>logoImage.png</uap:Logo>
            <uap:InfoTip>Detect MSIX Container</uap:InfoTip>
          </uap:FileTypeAssociation>
        </uap:Extension>
		  <uap:Extension Category="windows.protocol">
			  <uap:Protocol Name="wpfmsixdetect">
				  <uap:Logo>logoImage.png</uap:Logo>
				  <uap:DisplayName>WPF MSIX Detect</uap:DisplayName>
			  </uap:Protocol>
		  </uap:Extension>
		  <uap3:Extension Category="windows.appExecutionAlias" EntryPoint="windows.FullTrustApplication">
			  <uap3:AppExecutionAlias>
				  <desktop:ExecutionAlias Alias="wpfmsixdetect.exe"/>
			  </uap3:AppExecutionAlias>
		  </uap3:Extension>
		  </Extensions>