This is for Linux only. The steps to reproduce:
1. Focus in a text input control, invoke "Anthy" IME for Japanese
2. type string "suzukihonami" which contains 2 Japanese words
3. press "Space", the candidate window displays for the first words
4. press "Right" arrow key, then press "Space", the candidate window displays for the second words

During step 3 and step 4, the focused word in composing text should be highlighted or bold underline, but it was not.
Please compare how the IME works for Linux gedit and JavaFX TextArea with the attached videos, sysapp-ja-im.avi and textarea-ja-im.avi.