This is possible to enable this option by adding the following Spring bean definition in the applicationcontext-custom.xml file:
<bean class="org.jahia.services.uicomponents.bean.toolbar.Menu">
<property name="titleKey" value="label.publication"/>
<!-- <property name="icon" value="publicationAction"/> -->
<property name="items">
<list>
<ref bean="Toolbar.Item.PublishOne"/>
<ref bean="Toolbar.Item.PublishInAllLanguages"/>
<ref bean="Toolbar.Item.PublishAll"/>
<ref bean="Toolbar.Item.PublishAllInAllLanguages"/>
<ref bean="Toolbar.Item.PublishSite"/>
<ref bean="Toolbar.Item.PublishSiteInAllLanguages"/>
<ref bean="Toolbar.Item.Unpublish"/>
<ref bean="Toolbar.Item.ViewPublishStatus"/>
<ref bean="Toolbar.Item.PublicationManager"/>
</list>