Workaround for traditional/simplified Chinese conversion service

After converting simplified Chinese (example: 已估计) to traditional Chinese, the pasteboard sent to readSelectionFromPasteboard: contains several string types, but some of them will return nil, and the one we get back when using “public.plain-text” (“public.utf16-external-plain-text”) is one of these.

To enable the conversion service add both Traditional and Simplified Chinese as languages in System Preferences → Language & Region.