Hello Friends i want to make oe_chatter attachment option required in exiting view how i can do that. Please help me.

Here is the my try

<div class="oe_chatter">
    <field name="message_follower_ids" widget="mail_followers" groups="base.group_user" required="true"/>
    <field name="message_ids" widget="mail_thread" required='ture'/>
</div>