Customization of core doctypes

Can we customize core doctypes such as User in frappe

@NanduG you can if you are self hosted.

I don’t really understand the term self hosted here . What I really know is that I followed the process which is listed in the frappe official documentation for the set up and all and I was trying to customize the User doctype But it is showing core doctype is not customizable

@NanduG self hosted means not a server on frappe cloud , but your own server .
the way to customize core doctypes is to comment the code that restrict you from doing it . (frappe/custom/doctype/customize_form) . in js remove the filter code , and in python file remove the validate doctype function .
this will allow you to customize core doctypes in your own risk . then you can export them to a new app.
when installing the app to a new server you dont have to do the same editing .

No You can’t customize core doctype but if you edit it using development environment.