The patch supposedly just fixes “an issue when using an Energy Wall while equipped with certain pieces of developed gear,” according to the patch notes – although Konami also admits that it fixes “other issues” too.
According to players on Steam, the tiny 114 Mb patch is breaking all mod support for the game. Konami has issued a new patch for Metal Gear Solid V: The Phantom Pain on PC, and it has some unintended side effects – or very intended, depending on how you view Konami.