chore: upgrade to React 19 and update dev dependencies

- Update react, react-dom to v19; update @types/react, @types/react-dom to v19
- Remove react-test-renderer (deprecated in React 19)
- Update findDOMNode() in Draggable and DraggableCore to check nodeRef first,
  then fallback to ReactDOM.findDOMNode if available (for React 18 compat)
- Rewrite tests to use wrapper components that provide nodeRef (required in React 19)
- Update typings/test.tsx to use createRoot API instead of ReactDOM.render
- Update browser test HTML to use ES modules with importmap (React 19 removed UMD)
- Update all other dev dependencies to latest versions

Co-authored-by: Sculptor <sculptor@imbue.com>

Author: Samuel Reed

lib/Draggable.js

@@ -241,10 +241,17 @@ class Draggable extends React.Component<DraggableProps, DraggableState> {
     }
   }
 
-  // React Strict Mode compatibility: if `nodeRef` is passed, we will use it instead of trying to find
-  // the underlying DOM node ourselves. See the README for more information.
+  // React 19 removed ReactDOM.findDOMNode, so nodeRef is now required.
+  // For backward compatibility with React 18 and earlier, we still support findDOMNode if available.
   findDOMNode(): ?HTMLElement {
-    return this.props?.nodeRef?.current ?? ReactDOM.findDOMNode(this);
+    if (this.props?.nodeRef) {
+      return this.props.nodeRef.current;
+    }
+    // ReactDOM.findDOMNode was removed in React 19
+    if (typeof ReactDOM.findDOMNode === 'function') {
+      return ReactDOM.findDOMNode(this);
+    }
+    return null;
   }
 
   onDragStart: DraggableEventHandler = (e, coreData) => {

lib/DraggableCore.js

@@ -269,10 +269,22 @@ export default class DraggableCore extends React.Component<DraggableCoreProps> {
     }
   }
 
-  // React Strict Mode compatibility: if `nodeRef` is passed, we will use it instead of trying to find
-  // the underlying DOM node ourselves. See the README for more information.
+  // React 19 removed ReactDOM.findDOMNode, so nodeRef is now required.
+  // For backward compatibility with React 18 and earlier, we still support findDOMNode if available.
   findDOMNode(): ?HTMLElement {
-    return this.props?.nodeRef ? this.props?.nodeRef?.current : ReactDOM.findDOMNode(this);
+    if (this.props?.nodeRef) {
+      return this.props.nodeRef.current;
+    }
+    // ReactDOM.findDOMNode was removed in React 19
+    if (typeof ReactDOM.findDOMNode === 'function') {
+      return ReactDOM.findDOMNode(this);
+    }
+    // In React 19+, nodeRef is required - log a warning via our log utility
+    log(
+      'react-draggable: ReactDOM.findDOMNode is not available in React 19+. ' +
+      'You must provide a nodeRef prop. See: https://github.com/react-grid-layout/react-draggable#noderef'
+    );
+    return null;
   }
 
   handleDragStart: EventHandler<MouseTouchEvent> = (e) => {

package.json

@@ -52,31 +52,30 @@
     "@babel/preset-flow": "^7.27.1",
     "@babel/preset-react": "^7.28.5",
     "@eslint/eslintrc": "^3.3.3",
-    "@eslint/js": "^9.39.1",
+    "@eslint/js": "^9.39.2",
     "@testing-library/dom": "^10.4.1",
-    "@testing-library/react": "^16.3.0",
-    "@types/node": "^24.10.2",
-    "@types/react": "^18.2.23",
-    "@types/react-dom": "^18.2.8",
+    "@testing-library/react": "^16.3.1",
+    "@types/node": "^25.0.3",
+    "@types/react": "^19.2.7",
+    "@types/react-dom": "^19.2.3",
     "@vitejs/plugin-react": "^5.1.2",
     "babel-loader": "^10.0.0",
     "babel-plugin-transform-inline-environment-variables": "^0.4.4",
-    "eslint": "^9.39.1",
+    "eslint": "^9.39.2",
     "eslint-plugin-react": "^7.37.5",
     "flow-bin": "^0.217.0",
     "globals": "^16.5.0",
-    "jsdom": "^27.3.0",
+    "jsdom": "^27.4.0",
     "pre-commit": "^1.2.2",
     "process": "^0.11.10",
-    "puppeteer": "^24.32.1",
-    "react": "18",
-    "react-dom": "18",
+    "puppeteer": "^24.34.0",
+    "react": "19",
+    "react-dom": "19",
     "react-frame-component": "^5.2.7",
-    "react-test-renderer": "18",
     "semver": "^7.7.3",
     "typescript": "^5.9.3",
-    "vitest": "^4.0.15",
-    "webpack": "^5.103.0",
+    "vitest": "^4.0.16",
+    "webpack": "^5.104.1",
     "webpack-cli": "^6.0.1",
     "webpack-dev-server": "^5.2.2"
   },