Issue Summary

Duplicate characters are entered when create comment with Japanese with Safari.
It doesn't looks to occur in other browsers.

Steps to Reproduce

1. Open a issue with Safari browser
2. Switch to Japanese IME and type "toukyou" in comment

Expected Results

"とうきょう" is entered

Actual Results

"tととうとうkとうkyとうきょとうきょうとうきょう" is entered
画面収録 2020-07-27 9.51.59.mov

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available