Hide Buttons in Form View

In a submitted Sales Order, you can see buttons like Update Items , Status . Also there are many options under 'Create' button.

Custom Script

You can write custom script as shown below to hide these buttons.

frappe.ui.form.on('Sales Order', {
    refresh(frm) {
    setTimeout(() =&gt; {
        frm.remove_custom_button('Update Items');
        frm.remove_custom_button('Close', 'Status');
        frm.remove_custom_button('Work Order', 'Make');
        }, 10);
    }
})