This is a Visualforce component used to render Knockout.js HTML comment tags.

Visualforce: KnockoutJS Statement Component

<apex:component layout="none">

	<apex:attribute name="statement" 
			description="The Knockout containerless statement to insert."
			type="String"
			required="false"
	/>
	<apex:attribute name="close"
			description="Flag that determines whether this is an opening or closing statement for Knockout."
			type="Boolean"
			required="false"
			default="false"
	/>

	<apex:componentBody>
		<!--knockout opening tag-->
		<apex:outputPanel layout="none" rendered="{!NOT(ISBLANK(statement))}">
			<apex:outputText value="<" escape="false"/>!-- ko {!statement} --<apex:outputText value=">" escape="false"/>
		</apex:outputPanel>
		<!--knockout closing tag-->
		<apex:outputPanel layout="none" rendered="{!close}">
			<apex:outputText value="<" escape="false"/>!-- /ko --<apex:outputText value=">" escape="false"/>
		</apex:outputPanel>

	</apex:componentBody>

</apex:component>