</notebook>
</xpath>
<xpath expr="//notebook[@name='Volunteer activities']" position="after">
- <button string="Join membership" type="action" name="%(membership.action_membership_invoice_view)d"/>
+ <group attrs="{'invisible': [('membership_state', 'in', ['paid'])]}">
+ <button string="Join membership" type="action" name="%(membership.action_membership_invoice_view)d"/>
+ </group>
</xpath>
</field>
</record>