https://wiki.gnome.org/Projects/GLib/GDBus/Version2
The first four bytes of the header are defined the same way for dbus1
-and dbus2. The first bytes contain the endianess field and the
+and dbus2. The first bytes contain the endianness field and the
protocol version, so that the remainder of the message can be safely
made sense of just by looking at the first 32bit.