Twig DEFINE not working as expected

				<!-- DEFINE $MICRODATA = ' itemtype="http://data-vocabulary.org/Breadcrumb" itemscope=""' -->

				<li class="icon-home"><!-- IF U_SITE_HOME --><a href="{U_SITE_HOME}"{$MICRODATA}>{L_SITE_HOME}</a> <strong>&#8249;</strong> <!-- ENDIF -->

					<a href="{U_INDEX}" accesskey="h"{$MICRODATA}>{L_INDEX}</a> 

					<!-- BEGIN navlinks --> <strong>&#8249;</strong> <a href="{navlinks.U_VIEW_FORUM}"{$MICRODATA}>{navlinks.FORUM_NAME}</a><!-- END navlinks -->

					<!-- EVENT overall_header_breadcrumb_append -->

				</li>

								<li class="icon-home"><a href="https://area51.phpbb.com" itemtype=http://data-vocabulary.org/Breadcrumb itemscope=>Area51</a> <strong>&#8249;</strong> 					<a href="./index.php?sid=799cb114ea87ab136bca201f1a887256" accesskey="h" itemtype=http://data-vocabulary.org/Breadcrumb itemscope=>Board index</a> 

														</li>