Revert #3851 (#3878)

app/javascript/mastodon/components/status.js

@@ -91,14 +91,6 @@ class Status extends ImmutablePureComponent {
   }
 
   componentWillUnmount () {
-    if (!this.props.intersectionObserverWrapper) {
-      // TODO: enable IntersectionObserver optimization for notification statuses.
-      // These are managed in notifications/index.js rather than status_list.js
-      return;
-    }
-
-    this.props.intersectionObserverWrapper.unobserve(this.props.id, this.node);
-
     this.componentMounted = false;
   }
 

app/javascript/mastodon/features/ui/util/intersection_observer_wrapper.js

@@ -37,13 +37,6 @@ class IntersectionObserverWrapper {
     }
   }
 
-  unobserve (id, node) {
-    if (this.observer) {
-      delete this.callbacks[id];
-      this.observer.unobserve(node);
-    }
-  }
-
   disconnect () {
     if (this.observer) {
       this.observer.disconnect();