Unicode chars in variables show up as escape sequences after saving the var.
For example:

• Go to Config -> Maniphest
• Rename some status to a string containing non-ASCII symbols (e.g. Обычный)
• Save the value

The non-standard part will show up as \u041e\u0431\u044b\u0447\u043d\u044b\u0439 instead of Обычный.
Now if you'll try to edit the value again it will still show up as escape seq instead of wanted value. While saving it again won't break the existing text (e.g. escapes aren't thrown out), it's very hard to read/interpret/modify these values inside the configurator.