<field name="arch" type="xml">
<xpath expr="/form/notebook/page[@string='Extra Info']" position="before">
<page string="History">
- <field name="message_ids" colspan="4" nolabel="1" mode="tree,form">
+ <field name="message_ids" colspan="4" nolabel="1" mode="tree,form" readonly="1">
<tree string="History">
<field name="display_text" string="History Information"/>
</tree>