Add new language to Mac spell check

I’m transforming from MS word to use Page application on my Mac but I found out that there’s no Thai spell check by default. So I’ll have to add it manually. Here’s how I did it:

Firstly, download Thai dictionary (*.aff or *.dic) from https://github.com/tafasu/aegisub-thai-dict

Then copy to this folder

~/Library/Spelling

Restart, and go to System Preferences > Keyboard > Text > Spelling:

You should see your newly added langauge on the menu. Click on Set Up…

Now you can check the box for spelling with your prefer language.

Done, now I can spell check Thai on my Page application 😄