When I type commit message in Vietnamese (Unicode), some characters don't properly display. Please take a look at the attached picture.
An example message: "Đây là kí tự tiếng Việt"
Why don't you select such a font in the preferences?
I googled for that solution but did not get a good result. But after your comment, I can now find it. (Edit > Preferences > User interfaces > Built-in Text editors )
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