I am currently using the AnKing Note Types (Easy Customization) addon and there is no option to to not auto reveal the extra field. There is an option to disable it but non to not allow it auto reveal?
Hello, 
Unfortunately, I’m not aware of any way to do that, sorry to say. While it is possible to do this for other fields I’m not aware of any way to do it for the Extra field, specifically.
It may be possible if you’re comfortable tinkering with CSS code, though it’s also very possible that any code you alter would be overwritten by the add-on in short order.
In contrast, you can disable the field entirely if you like, and/or adjust the ordering in which your fields appear, though I suspect those are probably not as desirable as options.
Please let me know if that answers your question, and if there’s anything else I can help with.