Adding a new customfield in DocType which is not present in Customization Form

Hi Everyone
Can anyone let me know how we can add a new custom field in the doctype which is not show “Customize Form”. I am pointing about “Item Group” doctype. As new row is added to database from a click on “Add child” button on “Sales Browser” doctype. It opens up Dialog box and with 2 input fields. I want to add another field in it. But this doctype is not displayed in “Customize Form” doctypes. I know one way of adding the field is making changes from code, but it requires manually change in database schema which i cant perform it manually. Can any one me on these changes that how i can proceed.

I am using ERPNext V4 version.

Thanks in advance

That is hard coded. You will have to edit the sales browser page.

What is your use-case?

I am trying to add image in it to add logo for each parent “Item GRoup”

From Core → DocType → Item Group
i am able to add new column but still its not adding a new filed in database, So that i can make changes in Sales_browser.js file.