diff --git a/app/javascript/mastodon/containers/media_container.jsx b/app/javascript/mastodon/containers/media_container.jsx
index 25dc174444..f9244f8dd3 100644
--- a/app/javascript/mastodon/containers/media_container.jsx
+++ b/app/javascript/mastodon/containers/media_container.jsx
@@ -54,7 +54,7 @@ export default class MediaContainer extends PureComponent {
 
   handleCloseMedia = () => {
     document.body.classList.remove('with-modals--active');
-    document.documentElement.style.marginRight = 0;
+    document.documentElement.style.marginRight = '0';
 
     this.setState({
       media: null,
diff --git a/app/javascript/mastodon/features/ui/components/modal_root.jsx b/app/javascript/mastodon/features/ui/components/modal_root.jsx
index 5a17349771..c252e6caac 100644
--- a/app/javascript/mastodon/features/ui/components/modal_root.jsx
+++ b/app/javascript/mastodon/features/ui/components/modal_root.jsx
@@ -73,7 +73,7 @@ export default class ModalRoot extends React.PureComponent {
       document.documentElement.style.marginRight = `${getScrollbarWidth()}px`;
     } else {
       document.body.classList.remove('with-modals--active');
-      document.documentElement.style.marginRight = 0;
+      document.documentElement.style.marginRight = '0';
     }
   }