Updated to use refs rather than findNode as it's deprecated and was crashing in my usage.

Author: thaggie

.size-snapshot.json

@@ -1,12 +1,12 @@
 {
   "./lib/dist/react-transition-group.js": {
-    "bundled": 80859,
-    "minified": 22686,
-    "gzipped": 6939
+    "bundled": 82017,
+    "minified": 22806,
+    "gzipped": 7001
   },
   "./lib/dist/react-transition-group.min.js": {
-    "bundled": 46875,
-    "minified": 15056,
-    "gzipped": 4715
+    "bundled": 47393,
+    "minified": 15176,
+    "gzipped": 4768
   }
 }

src/Transition.js

@@ -1,6 +1,5 @@
 import * as PropTypes from 'prop-types'
 import React from 'react'
-import ReactDOM from 'react-dom'
 import { polyfill } from 'react-lifecycles-compat'
 
 import { timeoutsShape } from './utils/PropTypes'
@@ -140,6 +139,10 @@ class Transition extends React.Component {
     this.nextCallback = null
   }
 
+  setChildNode = node => {
+    this.childNode = node
+  }
+
   getChildContext() {
     return { transitionGroup: null } // allows for nested Transitions
   }
@@ -216,12 +219,13 @@ class Transition extends React.Component {
     if (nextStatus !== null) {
       // nextStatus will always be ENTERING or EXITING.
       this.cancelNextCallback()
-      const node = ReactDOM.findDOMNode(this)
-
-      if (nextStatus === ENTERING) {
-        this.performEnter(node, mounting)
-      } else {
-        this.performExit(node)
+      const node = this.childNode
+      if (node) {
+        if (nextStatus === ENTERING) {
+          this.performEnter(node, mounting)
+        } else {
+          this.performExit(node)
+        }
       }
     } else if (this.props.unmountOnExit && this.state.status === EXITED) {
       this.setState({ status: UNMOUNTED })
@@ -357,6 +361,8 @@ class Transition extends React.Component {
     delete childProps.onExiting
     delete childProps.onExited
 
+    childProps.ref = this.setChildNode
+
     if (typeof children === 'function') {
       return children(status, childProps)
     }