diff --git a/app/assets/javascripts/components/containers/mastodon.jsx b/app/assets/javascripts/components/containers/mastodon.jsx
index 6dc08bb4cdd..cbb7b85bcb9 100644
--- a/app/assets/javascripts/components/containers/mastodon.jsx
+++ b/app/assets/javascripts/components/containers/mastodon.jsx
@@ -46,6 +46,7 @@ import fr from 'react-intl/locale-data/fr';
 import pt from 'react-intl/locale-data/pt';
 import hu from 'react-intl/locale-data/hu';
 import uk from 'react-intl/locale-data/uk';
+import fi from 'react-intl/locale-data/fi';
 import getMessagesForLocale from '../locales';
 import { hydrateStore } from '../actions/store';
 import createStream from '../stream';
@@ -58,7 +59,7 @@ const browserHistory = useRouterHistory(createBrowserHistory)({
   basename: '/web'
 });
 
-addLocaleData([...en, ...de, ...es, ...fr, ...pt, ...hu, ...uk]);
+addLocaleData([...en, ...de, ...es, ...fr, ...pt, ...hu, ...uk, ...fi]);
 
 const Mastodon = React.createClass({