The `class` props should be `className` (#27462)

app/javascript/mastodon/features/ui/components/link_footer.jsx

@@ -100,7 +100,7 @@ class LinkFooter extends PureComponent {
           {DividingCircle}
           <a href={source_url} rel='noopener noreferrer' target='_blank'><FormattedMessage id='footer.source_code' defaultMessage='View source code' /></a>
           {DividingCircle}
-          <span class='version'>v{version}</span>
+          <span className='version'>v{version}</span>
         </p>
       </div>
     );

app/javascript/mastodon/features/ui/components/navigation_panel.jsx

@@ -59,10 +59,10 @@ class NavigationPanel extends Component {
           <Link to='/' className='column-link column-link--logo'><WordmarkLogo /></Link>
 
           {transientSingleColumn ? (
-            <div class='switch-to-advanced'>
+            <div className='switch-to-advanced'>
               {intl.formatMessage(messages.openedInClassicInterface)}
               {" "}
-              <a href={`/deck${location.pathname}`} class='switch-to-advanced__toggle'>
+              <a href={`/deck${location.pathname}`} className='switch-to-advanced__toggle'>
                 {intl.formatMessage(messages.advancedInterface)}
               </a>
             </div>