fix firefox empty target blank

src/template/player.art

@@ -255,7 +255,7 @@
 <div class="dplayer-menu">
     {{ each options.contextmenu }}
         <div class="dplayer-menu-item">
-            <a target="_blank" href="{{ $value.link || 'javascript:void(0);' }}">{{ tran($value.text) }}</a>
+            <a{{ if $value.link }} target="_blank"{{ /if }} href="{{ $value.link || 'javascript:void(0);' }}">{{ tran($value.text) }}</a>
         </div>
     {{ /each }}
 </div>