This fixes the behavior in notepad, with Japanese ibus-mozc IME, when typing "NIHONGO-SPACE-NO", or with Korean ibus-hangul when typing "GA-NA-DA". The latter still has an issue with the last character not appearing in the a composition but I believe it is unrelated to comctl32 and will be fixed by some future imm32 changes.
-- v5: user32/edit: Delegate composition string rendering to the IME UI. user32/edit: Notify IME on position, format_rect and font changes. comctl32/edit: Delegate composition string rendering to the IME UI. comctl32/edit: Notify IME on caret position, format_rect and font changes. imm32: Use DrawTextW to wrap IME composition string. imm32: Update the IME composition window position after drawing.