Performance improvements (#3168)

* refactor(components/status_list): Avoid quering scrollTop if not necessary

* refactor(components/dropdown_menu): Do not render items if not expanded

* refactor: Cherry-pick react-motion imports

* refactor(compose/privacy_dropdown): Do not render options if not open

* refactor(components/column_collapsable): Do not render children if collapsed

1 files changed, 2 insertions, 1 deletions

diff --git a/app/javascript/mastodon/features/ui/components/upload_area.js b/app/javascript/mastodon/features/ui/components/upload_area.js
index c7d109a33..c7f546588 100644
--- a/app/javascript/mastodon/features/ui/components/upload_area.js
+++ b/app/javascript/mastodon/features/ui/components/upload_area.js
@@ -1,6 +1,7 @@
 import React from 'react';
 import PropTypes from 'prop-types';
-import { Motion, spring } from 'react-motion';
+import Motion from 'react-motion/lib/Motion';
+import spring from 'react-motion/lib/spring';
 import { FormattedMessage } from 'react-intl';
 
 class UploadArea extends React.PureComponent {