dblclick default handler only when single click and dbl click are not false

Author: andrej-vasilj

src/components/legend/draw.js

@@ -476,7 +476,8 @@ function clickOrDoubleClick(gd, legend, legendItem, numClicks, evt) {
         gd._legendMouseDownTime = 0;
 
         var dblClickVal = Events.triggerHandler(gd, 'plotly_legenddoubleclick', evtData);
-        if(dblClickVal !== false) handleClick(legendItem, gd, numClicks);
+        // Activate default double click behaviour only when both single click and double click values are not false
+        if(dblClickVal !== false && clickVal !== false) handleClick(legendItem, gd, numClicks);
     }
 }