Document __unsafe_event__ for 7.x

Author: satya164

versioned_docs/version-7.x/navigation-container.md

@@ -304,6 +304,28 @@ const unsubscribe = navigationRef.addListener('__unsafe_action__', (e) => {
 
 It's only intended for debugging purposes and shouldn't be used for app logic.
 
+##### `__unsafe_event__`
+
+The event is triggered whenever an event is emitted by a navigator, and after all listeners have been called:
+
+```js
+const unsubscribe = navigationRef.addListener('__unsafe_event__', (e) => {
+  // The type of the event that was emitted
+  console.log(e.data.type);
+
+  // The data object passed when emitting the event
+  console.log(e.data.data);
+
+  // The key of the target route which received the event
+  console.log(e.data.target);
+
+  // Whether event.preventDefault() was called on this event
+  console.log(e.data.defaultPrevented);
+});
+```
+
+It's only intended for debugging purposes and shouldn't be used for app logic. To run app logic in response to an event, [listen to the event on the navigator level](navigation-events.md#listening-to-events) instead.
+
 ## Props
 
 ### `initialState`

versioned_docs/version-8.x/upgrading-from-7.x.md

@@ -1611,6 +1611,8 @@ const unsubscribe = navigationRef.addListener('__unsafe_event__', (e) => {
 
 This event is only intended for debugging purposes and shouldn't be used for app logic.
 
+This API has also been backported to React Navigation 7.
+
 See [NavigationContainer docs](navigation-container.md#__unsafe_event__) for more details.
 
 ### `useLogger` devtools now shows more information