diff --git a/lib/legacy/class.html b/lib/legacy/class.html
index 00e6a1bdcc..0872775db5 100644
--- a/lib/legacy/class.html
+++ b/lib/legacy/class.html
@@ -63,7 +63,6 @@
       return GenerateClassFromInfo({}, klass);
     }
 
-    
     function applyBehaviors(behaviors, klass) {
       if (!behaviors) {
         klass = /** @type {HTMLElement} */(klass); // eslint-disable-line no-self-assign
@@ -72,7 +71,7 @@
       // NOTE: ensure the behavior is extending a class with
       // legacy element api. This is necessary since behaviors expect to be able
       // to access 1.x legacy api.
-      klass = class extends Polymer.LegacyElementMixin(klass) {};
+      klass = class extends Polymer.LegacyElementMixin(klass) { };
       if (!Array.isArray(behaviors)) {
         behaviors = [behaviors];
       }
@@ -80,7 +79,7 @@
       // get flattened, deduped list of behaviors *not* already on super class
       behaviors = flattenBehaviors(behaviors, null, superBehaviors);
       // mixin new behaviors
-      klass = _applyBehaviors(behaviors, klass);
+      // klass = _applyBehaviors(behaviors, klass);
       if (superBehaviors) {
         behaviors = superBehaviors.concat(behaviors);
       }
@@ -120,14 +119,16 @@
     // (1) C.created, (2) A.created, (3) B.created, (4) element.created
     // (again same as 1.x)
     function _applyBehaviors(behaviors, klass) {
-      for (let i=0; i<behaviors.length; i++) {
-        let b = behaviors[i];
-        if (b) {
-          Array.isArray(b) ? _applyBehaviors(b, klass) :
-            copyProperties(b, klass.prototype);
+      if (behaviors) {
+        for (let i=0; i<behaviors.length; i++) {
+          let b = behaviors[i];
+          // if (b) {
+          //   Array.isArray(b) ? _applyBehaviors(b, klass) :
+              copyProperties(b, klass.prototype);
+          // }
         }
+        return klass;
       }
-      return klass;
     }
 
     /**
@@ -286,22 +287,25 @@
            in `beforeRegister` or `registered`. It is no longer possible to set
            `is` in `beforeRegister` as you could in 1.x.
           */
-          if (this.behaviors) {
-            for (let i=0, b; i < this.behaviors.length; i++) {
-              b = this.behaviors[i];
+          const proto = Object.getPrototypeOf(this);
+          _applyBehaviors(proto.behaviors, proto.constructor);
+          copyProperties(info, proto);
+          if (proto.behaviors) {
+            for (let i=0, b; i < proto.behaviors.length; i++) {
+              b = proto.behaviors[i];
               if (b.beforeRegister) {
-                b.beforeRegister.call(Object.getPrototypeOf(this));
+                b.beforeRegister.call(proto);
               }
               if (b.registered) {
-                b.registered.call(Object.getPrototypeOf(this));
+                b.registered.call(proto);
               }
             }
           }
           if (info.beforeRegister) {
-            info.beforeRegister.call(Object.getPrototypeOf(this));
+            info.beforeRegister.call(proto);
           }
           if (info.registered) {
-            info.registered.call(Object.getPrototypeOf(this));
+            info.registered.call(proto);
           }
         }
 
@@ -428,7 +432,7 @@
 
       PolymerGenerated.generatedFrom = info;
 
-      copyProperties(info, PolymerGenerated.prototype);
+      // copyProperties(info, PolymerGenerated.prototype);
 
       return PolymerGenerated;
     }