--- a/hgext3rd/topic/__init__.py	Tue Aug 23 23:38:28 2016 +0200
+++ b/hgext3rd/topic/__init__.py	Tue Aug 23 21:18:47 2016 +0200
@@ -336,7 +336,7 @@
     if not t:
         return
     # i18n: column positioning for "hg summary"
-    ui.write(_("topic:  %s\n") % t)
+    ui.write(_("topic:  %s\n") % ui.label(t, 'topic.active'))
 
 def commitwrap(orig, ui, repo, *args, **opts):
     with repo.wlock():