Intact default fields customization after update

Hi, I would like to know how can I intact customization implemented for the defaults fields like any change in columns width, print hide or default value change or any thing else.

If you need to edit default fields in any doctype you can do that just from Menu go to customize but not all changes you can make it. Only specifics things like make it mandatory… and you can add custom field and make it as you can
If you want to edit default. the pest way to do that should be in custom app . I hope i understand you and help .