Report [[User:Cwlin0416]]'s vandalism

The reason for Yue is similar for that so I oppose the Yue language to fallback to zh-Hant.

By the way MediaWiki never disabled the zh-CN/zh-TW interface so those languages can be translated if the translations are different to their parent language.

Never disabled? Although, per phab:T51898 there's a bypass way.

PS: If zh-hant is not an opinion then how about zh-hk?

On the other hand: "Classical Chinese fallback to the Traditional Chinese" not currently, see phab:T125373.

For example, the phrase "User" can both implemented in Chinese in General, so in both zh-Hant and zh-Hans should be use 『用戶』 and 『用户』 respectively. However in Taiwan terms, 『使用者』 are used more common so the term 『使用者』 should be translated in zh-TW instead of zh-Hant.

That's the similar terms "robot" or "bot" which differs between the Chinese Terms. In general, 『機器人』 or 『机器人』 are used in zh-Hant and zh-Hans respectively. In Hong Kong, the term 『機械人』 is used instead so this one should be translated in zh-HK but not for zh-Hant.