diff --git a/packages/react-diagrams-core/package.json b/packages/react-diagrams-core/package.json
index 09f5462..0a8cde6 100644
--- a/packages/react-diagrams-core/package.json
+++ b/packages/react-diagrams-core/package.json
@@ -37,5 +37,8 @@
 		"lodash": "4.*",
 		"react": "16.*"
 	},
-	"gitHead": "bb878657ba0c2f81764f32901fd96158a0f8352e"
+	"gitHead": "bb878657ba0c2f81764f32901fd96158a0f8352e",
+	"devDependencies": {
+		"resize-observer-polyfill": "^1.5.1"
+	}
 }
diff --git a/packages/react-diagrams-core/src/entities/node/NodeWidget.tsx b/packages/react-diagrams-core/src/entities/node/NodeWidget.tsx
index ce09f1f..271b268 100644
--- a/packages/react-diagrams-core/src/entities/node/NodeWidget.tsx
+++ b/packages/react-diagrams-core/src/entities/node/NodeWidget.tsx
@@ -4,6 +4,7 @@ import { DiagramEngine } from '../../DiagramEngine';
 import { NodeModel } from './NodeModel';
 import { BaseEntityEvent, BaseModel, ListenerHandle, PeformanceWidget } from '@projectstorm/react-canvas-core';
 import styled from '@emotion/styled';
+import ResizeObserver from 'resize-observer-polyfill';
 
 export interface NodeProps {
 	node: NodeModel;