edit components ReadOnly invalid via some input method

LineEdit is ReadOnly, and can input Chinese words or other thing(eng character, sentence) via input method (such as Win10 default chinese input method, sogou input method etc.)

I dont know if there are some problem with other input method of other language env.

and other user has the som problem.

Link to: https://forum.qt.io/topic/141443/text-still-can-be-input-to-qtextbrowser-in-readonly-mode-by-chinese-input-method