oca-technical/odoo-bringout-oca-rma-rma_sale/rma_sale/views/account_move_views.xml

<?xml version="1.0" encoding="utf-8" ?>
<odoo>
    <record id="view_move_form" model="ir.ui.view">
        <field name="name">account.move.form - Add helper sale_line_ids</field>
        <field name="model">account.move</field>
        <field name="inherit_id" ref="account.view_move_form" />
        <field name="arch" type="xml">
            <xpath expr="//field[@name='invoice_line_ids']/tree" position="inside">
                <field name="sale_line_ids" readonly="0" invisible="1" />
            </xpath>
            <xpath expr="//field[@name='line_ids']/tree" position="inside">
                <field name="sale_line_ids" readonly="0" invisible="1" />
            </xpath>
        </field>
    </record>
</odoo>