In flat_left.tpl of ezwebin, line 4 is as follows:

<h4><a href=

{if eq( $ui_context, 'browse' )} {concat("content/browse/", $module_result.path[$pagerootdepth].node_id)|ezurl} {else}

{$module_result.path[$pagerootdepth].url_alias|ezurl}

{/if}

>{$module_result.path[$pagerootdepth].text}</a></h4>

However if $module_result.path[$pagerootdepth] is current page then it will instead link to rootpage of site, as .url_alias for last item in $module_result.path is set to false.

Additional comment: documentation at http://ez.no/doc/ez_publish/technical_manual/3_9/templates/the_pagelayout/variables_in_pagelayout#module_result
does not mention .node_id and .url_alias at all and says "The "url" key of the last element in the array is usually set to false."

Using the word "usually" in such place kind of bothers me..

Steps to reproduce

Browse to first level subfolder of site that has left menu active.