Index: lams_central/web/includes/javascript/authoring/authoringActivity.js
===================================================================
diff -u -r4f01dc291e2a756de97ba01e790754b3a3d0fecf -r92d270ee0e95593827ee5c0f7aabba57c1ab285a
--- lams_central/web/includes/javascript/authoring/authoringActivity.js	(.../authoringActivity.js)	(revision 4f01dc291e2a756de97ba01e790754b3a3d0fecf)
+++ lams_central/web/includes/javascript/authoring/authoringActivity.js	(.../authoringActivity.js)	(revision 92d270ee0e95593827ee5c0f7aabba57c1ab285a)
@@ -1346,11 +1346,16 @@
 		});
 	},
 	
-
+	
 	/**
 	 * Open separate window with activity authoring on double click.
 	 */
 	openActivityAuthoring : function(activity){
+		if (activity.isAuthoringOpening) {
+			return;
+		}
+		
+		activity.isAuthoringOpening = true;
 		if (activity.authorURL) {
 			showDialog("dialogActivity" + activity.toolContentID, {
 				'height' : Math.max(300, $(window).height() - 30),
@@ -1388,10 +1393,11 @@
 			}, true);
 			
 			GeneralLib.setModified(true);
+			activity.isAuthoringOpening = false;
 			return;
 		}
 		
-		// if there is not authoring URL, fetch it for a Tool Activity
+		// if there is no authoring URL, fetch it for a Tool Activity
 		if (activity.toolID) {
 			$.ajax({
 				async : true,
@@ -1415,11 +1421,17 @@
 							layout.ld.contentFolderID = response.contentFolderID;
 						}
 						
+						activity.isAuthoringOpening = false;
 						// this time open it properly
 						ActivityLib.openActivityAuthoring(activity);
 					}
+				},
+				complete : function(){
+					activity.isAuthoringOpening = false;
 				}
 			});
+		} else {
+			activity.isAuthoringOpening = false;
 		}
 	},