Custom Action in Link Field

You can add a new custom link option to the standard link field by defining the function in the namespace frappe.ui.form.ControlLink.link_options.

In the frappe.ui.form.ControlLink.link_options, you have access to the link field object.

1. Adding Custom Option

frappe.ui.form.ControlLink.link_options = function(link) {
 return [
 {
 html: ""
 + " "
 + __("Custom Link Option")
 + "",
 label: __("Custom Link Option"),
 value: "custom__link_option",
 action: () => {}
 }
 ];
}

Once a function is assigned to frappe.ui.form.ControlLink.link_options, the link field will have a new link option: