Restore vanilla components

app/javascript/mastodon/components/column_back_button_slim.js

@@ -0,0 +1,27 @@
+import React from 'react';
+import { FormattedMessage } from 'react-intl';
+import PropTypes from 'prop-types';
+
+export default class ColumnBackButtonSlim extends React.PureComponent {
+
+  static contextTypes = {
+    router: PropTypes.object,
+  };
+
+  handleClick = () => {
+    if (window.history && window.history.length === 1) this.context.router.history.push('/');
+    else this.context.router.history.goBack();
+  }
+
+  render () {
+    return (
+      <div className='column-back-button--slim'>
+        <div role='button' tabIndex='0' onClick={this.handleClick} className='column-back-button column-back-button--slim-button'>
+          <i className='fa fa-fw fa-chevron-left column-back-button__icon' />
+          <FormattedMessage id='column_back_button.label' defaultMessage='Back' />
+        </div>
+      </div>
+    );
+  }
+
+}