Japanese keyboard became slower

Hello everyone!

I bought a macbook air recently, and I use the Japanese keyboard a lot, and every time I'm typing, it is taking ages to load to write because it's loading so slowly the kanji entrees. I didn't have any of those problem before, but it seems to have become worst since a few updates ago.

When I use the Google IME keyboard, there's absolutely no loading, but I don't like how it works, and I'd like to use the one mac offers.

If you have any way to stop this loading, it would be great! 🙂