He recounted how a friend of his was unable to type "Taiwan" in her phone for two years without a particular app crashing. After analyzing the crash data, Wardle found the device would crash because of a memory error in how the operating system processes and removes certain emojis when a device's region is not correctly set.
In doing so, it would return a "null" value, which caused the crash.
In case you didn't know, Apple removes certain emojis at China's request. In the case of Taiwan, China's relationship with the territory is fraught at best. China claims the country as its territory, but Taiwan claims it has the right to self-govern. China, as it often does, responded with censorship. It's believed that Apple removed the Taiwanese flag emoji from Chinese-language iPhones as if the country doesn't exist.
Anyone with that language setting wouldn't see the emoji but would instead see a square with a cross through it.
Simply switching the region back again would fix the issue. Mystery solved.
Apple did not immediately respond to a request for comment.