Description:
In Writer 6.2 rc2, it is okay to input under normal mode.  However when inputting in a text block, the behavior is strange:

* Inputting English was okay.
* When inputting Chinese (via input method), the first Chinese character would be "eaten" and was not shown.  The second Chinese character could be shown.
* After pressing Enter to next (several) lines, when I input another Chinese character the cursor would jump back to the position of last Chinese character.
* If I input English characters at the previous step then there was nothing weird.  But when I use Ctrl-Space again to switch my input method to Chinese input mode, the cursor jumped back again.

In Impress and Draw the behavior of inputting in a text block was the similar, except the first Chinese character wouldn't be eaten.

Steps to Reproduce:
1. Open Writer 6.2 rc2 and insert a text block.
2. Input a Chinese character via input method (my IM engine is gcin)
3. The first Chinese character would be eaten, but the characters afterwards can be shown
4. Press Enter (one or several times)
5. Input another Chinese character again
6. The cursor would jump back to the position of last Chinese character and new character would be shown in the same line

Actual Results:
* In Writer the first Chinese character input in a text block would be gone, and others would be shown.
* Pressing Enter to change line was useless since when inputting another Chinese character the cursor would jump back.
* In Impress and Draw the first Chinese character would be shown correctly, but changing lines was still useless.

Expected Results:
It should act normally


Reproducible: Always


User Profile Reset: Yes



Additional Info:
Only happened in VCL kde5 backend.
kde4 and gtk3 would not happen.