What do you mean, "you have to set it explicitly and several issues may occur"?
I have a situation when inputting into an editable ComboBox and desiring Autocomplete functionality via Chinese IME input--only the first character will result in the text field leading Autocomplete simply to the first instance of a word starting with that character. Thus afterward the user must scroll to the exact word they seek. This would be akin to typing in "Telerik" and only the "T" appearing and autocomplete going to the first instance of names starting with "T," thus having to scroll past all the T names until coming to "Telerik."
The user workaround is to type several keystrokes for the first character, hit "Enter;" type several more keystrokes for the second character, hit "Enter;" type several more keystrokes for the third character, hit "Enter"... This akin to typing T-enter; e-enter, l-enter, e-enter, r-enter, i-enter, k-enter to type Telerik. This isn't normal Chinese behavior and bad user experience.
Is this already a known issue? Is there a solution or technical workaround? Any suggestions?