Apple has confirmed that it will be fixing an issue that causes the iPhone X screen to suddenly become unresponsive in cold weather. The fix will arrive in the form of a software update, in a new version of iOS.
Attention to the problem appears to have surfaced from the iPhone subreddit community discussion recently. In that discussion, several iPhone X users complained about the keyboard and touchscreen malfunctioning in cold temperatures. However, some of the iPhone X owners said that it worked after locking and unlocking the device again.