James Luo - 2018-01-11

I want to confirm is the undo function is working properly on CJK or not.
When I use texworks and WinEdt, after I input Chinese characters, if I undo the input, it undo all the input.

However in TexStudio, the undo will first convert the Chinese characters to Pinyin (alphabet chars), and then I have to press Ctrl-Z a lot of times to undo every chars.

Is such a behaviour normal?