Improve style property updates

src/style_manager/model/Property.js

@@ -73,7 +73,9 @@ const Property = Backbone.Model.extend(
      */
     setValue(value, complete = 1, opts = {}) {
       const parsed = this.parseValue(value);
-      this.set(parsed, { ...opts, avoidStore: !complete });
+      const avoidStore = !complete;
+      !avoidStore && this.set({ value: '' }, { avoidStore, silent: true });
+      this.set(parsed, { ...opts, avoidStore });
     },
 
     /**

src/style_manager/view/PropertyView.js

@@ -469,6 +469,13 @@ export default Backbone.View.extend({
       delete style[property];
     }
 
+    // Forces to trigger the change (for UndoManager)
+    if (opts.avoidStore) {
+      style.__ = 1;
+    } else {
+      delete style.__;
+    }
+
     target.setStyle(style, opts);
 
     // Helper is used by `states` like ':hover' to show its preview