[$] X clients and byte swapping

While there are still systems with both byte orders,little-endian has largely "won" the battle at this point since the vast majority of today'ssystems store data with the least-significant byte first (at the lowestaddress). But when the X11 protocol was developed in the 1980s, there were lots of systems of each byte order, so the X protocol allowed either orderand the server (display side) would swap the bytes to its byte order asneeded. Over time, the code for swapping data in the messages, which was written in amore-trusting era, has bit-rotted so that it is now alargely untested attack surface that is nearly always unused. PeterHutterer has been doing some work to stop using that code by default, bothin upstream X.org code and in downstream Fedora.