web/web_chatter_position/static/src/xml/form_buttons.xml

<?xml version="1.0" encoding="utf-8" ?>
<templates id="form_view" xml:space="preserve">
    <t t-extend="FormView.buttons">
        <t t-jquery=".o_form_button_edit" t-operation="before">
            <button type="button" class="btn btn-secondary o_chatter_position_button">
                <i class="fa fa-arrows-h" />
            </button>
        </t>
        <t t-jquery=".o_form_button_save" t-operation="before">
            <button type="button" class="btn btn-secondary o_chatter_position_button">
                <i class="fa fa-arrows-h" />
            </button>
        </t>
    </t>
</templates>