diff --git a/cvat/apps/engine/annotation.py b/cvat/apps/engine/annotation.py
index c2a13b1e292a..862ef2913c03 100644
--- a/cvat/apps/engine/annotation.py
+++ b/cvat/apps/engine/annotation.py
@@ -165,7 +165,7 @@ class dotdict(OrderedDict):
 
         for key in keys_for_merge:
             item = dotdict({v.split('__', 1)[-1]:row[v] for v in keys_for_merge[key]})
-            if item.id:
+            if item.id is not None:
                 merged_rows[row_id][key].append(item)
 
     # Remove redundant keys from final objects
@@ -556,6 +556,14 @@ def _init_tracks_from_db(self):
                 ]
             }, 'id')
 
+            # A result table can consist many equal rows for track/shape attributes
+            # We need filter unique attributes manually
+            db_track["labeledtrackattributeval_set"] = list(set(db_track["labeledtrackattributeval_set"]))
+            for db_shape in db_track["trackedshape_set"]:
+                db_shape["trackedshapeattributeval_set"] = list(
+                    set(db_shape["trackedshapeattributeval_set"])
+                )
+
         serializer = serializers.LabeledTrackSerializer(db_tracks, many=True)
         self.data["tracks"] = serializer.data
 
@@ -924,8 +932,9 @@ def to_tracks(self):
             shape0 = copy.copy(shape)
             shape0["keyframe"] = True
             shape0["outside"] = False
+            # TODO: Separate attributes on mutable and unmutable
+            shape0["attributes"] = []
             shape0.pop("group", None)
-            shape0.pop("attributes")
             shape1 = copy.copy(shape0)
             shape1["outside"] = True
             shape1["frame"] += 1
@@ -1099,15 +1108,17 @@ def interpolate(shape0, shape1):
         curr_frame = track["shapes"][0]["frame"]
         prev_shape = {}
         for shape in track["shapes"]:
-            if shape["frame"] != curr_frame:
+            if prev_shape:
                 assert shape["frame"] > curr_frame
+                for attr in prev_shape["attributes"]:
+                    if attr["spec_id"] not in map(lambda el: el["spec_id"], shape["attributes"]):
+                        shape["attributes"].append(copy.deepcopy(attr))
                 if not prev_shape["outside"]:
                     shapes.extend(interpolate(prev_shape, shape))
 
-            if not shape["outside"]:
-                shape["keyframe"] = True
-                shapes.append(shape)
-            curr_frame = shape["frame"] + 1
+            shape["keyframe"] = True
+            shapes.append(shape)
+            curr_frame = shape["frame"]
             prev_shape = shape
 
         # TODO: Need to modify a client and a database (append "outside" shapes for polytracks)
diff --git a/cvat/apps/engine/static/engine/js/annotationSaver.js b/cvat/apps/engine/static/engine/js/annotationSaver.js
index 40759d8d5ab3..b3ce668dc3fb 100644
--- a/cvat/apps/engine/static/engine/js/annotationSaver.js
+++ b/cvat/apps/engine/static/engine/js/annotationSaver.js
@@ -24,11 +24,14 @@ class AnnotationSaverModel extends Listener {
 
         this._hash = this._getHash();
 
-        for (const shape of initialData.shapes) {
+        // We need use data from export instead of initialData
+        // Otherwise we have differ keys order and JSON comparison code incorrect
+        const data = this._shapeCollection.export()[0];
+        for (const shape of data.shapes) {
             this._initialObjects[shape.id] = shape;
         }
 
-        for (const track of initialData.tracks) {
+        for (const track of data.tracks) {
             this._initialObjects[track.id] = track;
         }
     }
@@ -177,6 +180,7 @@ class AnnotationSaverModel extends Listener {
     }
 
     _updateCreatedObjects(objectsToSave, savedObjects, mapping) {
+        // Method setups IDs of created objects after saving on a server
         const allSavedObjects = savedObjects.shapes.concat(savedObjects.tracks);
         const allObjectsToSave = objectsToSave.shapes.concat(objectsToSave.tracks);
         if (allSavedObjects.length !== allObjectsToSave.length) {
@@ -185,7 +189,9 @@ class AnnotationSaverModel extends Listener {
 
         for (let idx = 0; idx < allSavedObjects.length; idx += 1) {
             const objectModel = mapping.filter(el => el[0] === allObjectsToSave[idx])[0][1];
-            objectModel.serverID = allSavedObjects[idx].id;
+            const { id } = allSavedObjects[idx];
+            objectModel.serverID = id;
+            allObjectsToSave[idx].id = id;
         }
 
         this._shapeCollection.update();
@@ -218,6 +224,7 @@ class AnnotationSaverModel extends Listener {
                 const savedObjects = await this._put(data);
                 this._updateCreatedObjects(exported, savedObjects, mapping);
                 this._shapeCollection.flush = false;
+                this._version = savedObjects.version;
                 for (const object of savedObjects.shapes.concat(savedObjects.tracks)) {
                     this._initialObjects[object.id] = object;
                 }
@@ -228,13 +235,15 @@ class AnnotationSaverModel extends Listener {
                 this.notify('saveCreated');
                 const savedCreated = await this._create(created);
                 this._updateCreatedObjects(created, savedCreated, mapping);
-                for (const object of savedCreated.shapes.concat(savedCreated.tracks)) {
+                this._version = savedCreated.version;
+                for (const object of created.shapes.concat(created.tracks)) {
                     this._initialObjects[object.id] = object;
                 }
 
                 this.notify('saveUpdated');
                 const savedUpdated = await this._update(updated);
-                for (const object of savedUpdated.shapes.concat(savedUpdated.tracks)) {
+                this._version = savedUpdated.version;
+                for (const object of updated.shapes.concat(updated.tracks)) {
                     if (object.id in this._initialObjects) {
                         this._initialObjects[object.id] = object;
                     }
@@ -242,6 +251,7 @@ class AnnotationSaverModel extends Listener {
 
                 this.notify('saveDeleted');
                 const savedDeleted = await this._delete(deleted);
+                this._version = savedDeleted.version;
                 for (const object of savedDeleted.shapes.concat(savedDeleted.tracks)) {
                     if (object.id in this._initialObjects) {
                         delete this._initialObjects[object.id];