UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/66.0.3359.181 Safari/537.36

Steps to reproduce the problem:
1. Turn IME(MS IME or ATOK or Google日本語入力) on and input some Japanese texts in a DIV element which is contenteditable and its writing-mode is vertical-rl.
2. The candidate window hovers over texts.
3. You can't see texts well.

What is the expected behavior?
The candidate window should show at the bottom of texts.

What went wrong?
The candidate window hovers over texts.

Did this work before? N/A 

Does this work in other browsers? Yes

Chrome version: 66.0.3359.181  Channel: stable
OS Version: 10.0
Flash Version: Shockwave Flash 29.0 r0

I know Chrome doesn't support writing-mode:vertical-rl for input:type:text. I would like to the candicate window shows well also when Chrome supports it.
 

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