diff --git a/.codeclimate.yml b/.codeclimate.yml
new file mode 100644
index 00000000..abd4ff1c
--- /dev/null
+++ b/.codeclimate.yml
@@ -0,0 +1,26 @@
+languages:
+  JavaScript: true
+engines:
+  eslint:
+    enabled: true
+  csslint:
+    enabled: true
+  markdownlint:
+    enabled: true
+  duplication:
+    enabled: true
+    config:
+      languages:
+        javascript:
+          mass_threshold: 300
+  fixme :
+    enabled: true
+ratings:
+  paths:
+  - "**/*.js"
+  - "**/*.css"
+  - "**/*.md"
+exclude_paths:
+  - "dist/**/*"
+  - "docs/**/*"
+  - "examples/**/*"
diff --git a/.csslintrc b/.csslintrc
new file mode 100644
index 00000000..2b014c6a
--- /dev/null
+++ b/.csslintrc
@@ -0,0 +1,6 @@
+{
+  "adjoining-classes": false,
+  "box-model": false,
+  "box-sizing": false,
+  "order-alphabetical": false
+}
diff --git a/.eslintrc b/.eslintrc
new file mode 100644
index 00000000..00d60a6e
--- /dev/null
+++ b/.eslintrc
@@ -0,0 +1,6 @@
+{
+  "rules": {
+    "complexity": [2, 50],
+    "max-statements": [2, 100]
+  }
+}
diff --git a/.mdlrc b/.mdlrc
new file mode 100644
index 00000000..bb5535c3
--- /dev/null
+++ b/.mdlrc
@@ -0,0 +1,7 @@
+// Markdown Lint Rules
+// https://github.com/mivok/markdownlint/blob/master/docs/RULES.md
+
+rules
+  "~MD012", // alert on multiple consecutive blank lines
+  "~MD013", // line length should be no more than 80 characters
+  "~MD014", // Dollar signs used before commands without showing output
diff --git a/HISTORY.md b/HISTORY.md
index 0b7bad0d..e588235e 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -14,7 +14,7 @@ http://visjs.org
 - Fixed #2170: Improved the contribution docs (#1991, #2158, #2178, #2183, #2213, #2218, #2219)
 - Implemented #1969: generate individual css files for network and timeline (#1970)
 - Cleanup bower.json (#1968)
-- Removed feature-request page from website (TODO)
+- Fixed #2114: Removed feature-request page from website
 - Distinguish better between `devDependencies` and `dependencies` (#1967)
 - Typos and minor docs improvements (#1958, #2028, #2050, #2093, #2222, #2223, #2224)
 - Replaced `gulp-minify-css` with `gulp-clean-css` (#1953)
@@ -266,7 +266,7 @@ http://visjs.org
 ### General
 
 - Fixed #1353: Custom bundling with browserify requiring manual installation
-  of `babelify`.  
+  of `babelify`.
 
 ### Network
 
@@ -451,7 +451,7 @@ http://visjs.org
 - Fixed #1033: Moved item data not updated in DataSet when using an asynchronous
   `onMove` handler.
 - Fixed #239: Do not zoom/move the window when the mouse is on the left panel
-  with group labels.   
+  with group labels.
 
 
 ## 2015-07-03, version 4.4.0
diff --git a/examples/timeline/other/drag&drop.html b/examples/timeline/other/drag&drop.html
index 81bcb1f1..5810eb9b 100644
--- a/examples/timeline/other/drag&drop.html
+++ b/examples/timeline/other/drag&drop.html
@@ -49,6 +49,10 @@
     <li draggable="true" class="item">
       item 3 - range
     </li>
+    <li draggable="true" class="item">
+      item 3 - range - fixed times - <br>
+      (start: now, end: now + 10 min)
+    </li>
   </ul>
 </div>
 
@@ -110,12 +114,16 @@
     var item = {
       id: new Date(),
       type: itemType,
-      content: event.target.innerHTML.split('-')[0].trim(),
-      start: new Date(),
-      end: new Date(1000*60*60*24 + (new Date()).valueOf()),
+      content: event.target.innerHTML.split('-')[0].trim()
     };
 
-    event.dataTransfer.setData("text/plain", JSON.stringify(item));
+    var isFixedTimes = (event.target.innerHTML.split('-')[2] && event.target.innerHTML.split('-')[2].trim() == 'fixed times')
+    if (isFixedTimes) {
+      item.start = new Date();
+      item.end = new Date(1000*60*10 + (new Date()).valueOf());
+    }
+
+    event.dataTransfer.setData("text", JSON.stringify(item));
   }
 
   var items = document.querySelectorAll('.items .item');
diff --git a/gulpfile.js b/gulpfile.js
index 697185d3..05bf2bc3 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -8,7 +8,6 @@ var rename = require("gulp-rename");
 var webpack = require('webpack');
 var uglify = require('uglify-js');
 var rimraf = require('rimraf');
-var merge = require('merge-stream');
 var argv = require('yargs').argv;
 
 var ENTRY             = './index.js';
diff --git a/lib/timeline/Core.js b/lib/timeline/Core.js
index aa8344da..a5034479 100644
--- a/lib/timeline/Core.js
+++ b/lib/timeline/Core.js
@@ -231,7 +231,7 @@ Core.prototype._create = function (container) {
     }
 
     // make sure your target is a vis element
-    if (!event.target.className.includes('vis')) return;
+    if (!event.target.className.indexOf("vis") > -1) return;
 
     // make sure only one item is added every time you're over the timeline
     if (itemAddedToTimeline) return;
@@ -244,7 +244,7 @@ Core.prototype._create = function (container) {
   function handleDrop(event) {
     // return when dropping non-vis items 
     try {
-      var itemData = JSON.parse(event.dataTransfer.getData("text/plain"))
+      var itemData = JSON.parse(event.dataTransfer.getData("text"))
       if (!itemData.content) return
     } catch (err) {
       return false;
@@ -252,8 +252,8 @@ Core.prototype._create = function (container) {
 
     itemAddedToTimeline = false;
     event.center = {
-      x: event.x,
-      y: event.y
+      x: event.clientX,
+      y: event.clientY
     }
     me.itemSet._onAddItem(event);
 
diff --git a/lib/timeline/component/ItemSet.js b/lib/timeline/component/ItemSet.js
index ed27f48a..b0a71b94 100644
--- a/lib/timeline/component/ItemSet.js
+++ b/lib/timeline/component/ItemSet.js
@@ -243,7 +243,7 @@ ItemSet.prototype._create = function(){
   this.groupHammer.on('panstart', this._onGroupDragStart.bind(this));
   this.groupHammer.on('panmove',  this._onGroupDrag.bind(this));
   this.groupHammer.on('panend',   this._onGroupDragEnd.bind(this));
-  this.groupHammer.get('pan').set({threshold:5, direction: Hammer.DIRECTION_HORIZONTAL});
+  this.groupHammer.get('pan').set({threshold:5, direction: Hammer.DIRECTION_VERTICAL});
   
   this.body.dom.centerContainer.addEventListener('mouseover', this._onMouseOver.bind(this));
   this.body.dom.centerContainer.addEventListener('mouseout', this._onMouseOut.bind(this));
@@ -1578,6 +1578,10 @@ ItemSet.prototype._onGroupDrag = function (event) {
 	if (this.options.groupEditable.order && this.groupTouchParams.group) {
 		event.stopPropagation();
 		
+    var groupsData = this.groupsData;
+    if (this.groupsData instanceof DataView) {
+      groupsData = this.groupsData.getDataSet()
+    }
 		// drag from one group to another
 		var group = this.groupFromTarget(event);
 		
@@ -1602,25 +1606,23 @@ ItemSet.prototype._onGroupDrag = function (event) {
 		}
 		
 		if (group && group != this.groupTouchParams.group) {
-			var groupsData = this.groupsData;
 			var targetGroup = groupsData.get(group.groupId);
 			var draggedGroup = groupsData.get(this.groupTouchParams.group.groupId);
 			
 			// switch groups
 			if (draggedGroup && targetGroup) {
 				this.options.groupOrderSwap(draggedGroup, targetGroup, this.groupsData);
-				this.groupsData.update(draggedGroup);
-				this.groupsData.update(targetGroup);
+  				groupsData.update(draggedGroup);
+        			groupsData.update(targetGroup);
 			}
 			
 			// fetch current order of groups
-			var newOrder = this.groupsData.getIds({
+			var newOrder = groupsData.getIds({
 			    order: this.options.groupOrder
-		    });
+		    	});
 			
 			// in case of changes since _onGroupDragStart
 			if (!util.equalArray(newOrder, this.groupTouchParams.originalOrder)) {
-				var groupsData = this.groupsData;
 				var origOrder = this.groupTouchParams.originalOrder;
 				var draggedId = this.groupTouchParams.group.groupId;
 				var numGroups = Math.min(origOrder.length, newOrder.length);
@@ -1854,12 +1856,12 @@ ItemSet.prototype._onAddItem = function (event) {
       newItemData[this.itemsData._fieldId] = itemData.id || util.randomUUID();
 
       if (itemData.type == 'range' || (itemData.end && itemData.start)) {
-
         if (!itemData.end) {
           var end = this.body.util.toTime(x + this.props.width / 5);
           newItemData.end = snap ? snap(end, scale, step) : end;
         } else {
-          newItemData.end = new Date(newItemData.start._i).getTime() + new Date(itemData.end).getTime() - new Date(itemData.start).getTime();
+          newItemData.end = itemData.end;
+          newItemData.start = itemData.start;
         }
       }
     } else {
diff --git a/lib/util.js b/lib/util.js
index 22deac1d..54d68bf7 100644
--- a/lib/util.js
+++ b/lib/util.js
@@ -1488,17 +1488,19 @@ exports.topMost = function (pile, accessors) {
     accessors = [accessors];
   }
   for (const member of pile) {
-    candidate = member[accessors[0]];
-    for (let i = 1; i < accessors.length; i++){
+    if (member) {
+      candidate = member[accessors[0]];
+      for (let i = 1; i < accessors.length; i++){
+        if (candidate) {
+          candidate = candidate[accessors[i]]
+        } else {
+          continue;
+        }
+      }
       if (candidate) {
-        candidate = candidate[accessors[i]]
-      } else {
-        continue;
+        break;
       }
     }
-    if (candidate) {
-      break;
-    }
   }
   return candidate;
-}
+};
diff --git a/package.json b/package.json
index 5d22df48..93c24982 100644
--- a/package.json
+++ b/package.json
@@ -47,7 +47,6 @@
     "gulp-concat": "^2.6.0",
     "gulp-rename": "^1.2.2",
     "gulp-util": "^3.0.7",
-    "merge-stream": "^1.0.0",
     "mocha": "^3.1.2",
     "rimraf": "^2.5.2",
     "uglify-js": "^2.6.2",