remove workaround for #444 and phetsims/fractions-common#19

js/AccordionBox.js

@@ -246,13 +246,6 @@ define( function( require ) {
         } );
       }
     }
-    else {
-      // If we don't show the title when expanded, we won't want our title bar to be pickable. Ideally we wouldn't want
-      // it visible at all, however for the a11y implementation we'll want to keep it visible so it can be focused as
-      // the main accessible element while the accordion box is expanded.
-      // See https://github.com/phetsims/fractions-common/issues/19.
-      this.expandedTitleBar.pickable = false;
-    }
 
     this.addChild( this.titleNode );
     this.addChild( this.expandCollapseButton );