Thank you for your reply. I am Chinese, and my site is a Chinese site. My default language for the site is Chinese (TW). However, some users register usernames using English letters. For example, “zgzud” is just a username; it is not my Chinese name, nor is it a Chinese name.
I am still quite confused. Which approach would you recommend? Is “Changing the setting to 2 is OK,” or is “Changing the setting to 4 or 5 is better”? Thank you!