diff --git a/app/javascript/mastodon/components/extended_video_player.js b/app/javascript/mastodon/components/extended_video_player.js
index 4c62fa7b3df..b38a4b8ff11 100644
--- a/app/javascript/mastodon/components/extended_video_player.js
+++ b/app/javascript/mastodon/components/extended_video_player.js
@@ -5,6 +5,8 @@ export default class ExtendedVideoPlayer extends React.PureComponent {
 
   static propTypes = {
     src: PropTypes.string.isRequired,
+    width: PropTypes.number,
+    height: PropTypes.number,
     time: PropTypes.number,
     controls: PropTypes.bool.isRequired,
     muted: PropTypes.bool.isRequired,
@@ -30,7 +32,7 @@ export default class ExtendedVideoPlayer extends React.PureComponent {
 
   render () {
     return (
-      <div className='extended-video-player'>
+      <div className='extended-video-player' style={{ width: this.props.width, height: this.props.height }}>
         <video
           ref={this.setRef}
           src={this.props.src}
diff --git a/app/javascript/mastodon/features/ui/components/media_modal.js b/app/javascript/mastodon/features/ui/components/media_modal.js
index d869fffa677..dcc9becd35b 100644
--- a/app/javascript/mastodon/features/ui/components/media_modal.js
+++ b/app/javascript/mastodon/features/ui/components/media_modal.js
@@ -65,8 +65,6 @@ export default class MediaModal extends ImmutablePureComponent {
     const { media, intl, onClose } = this.props;
 
     const index = this.getIndex();
-    const attachment = media.get(index);
-    const url = attachment.get('url');
 
     let leftNav, rightNav, content;
 
@@ -77,16 +75,18 @@ export default class MediaModal extends ImmutablePureComponent {
       rightNav = <div role='button' tabIndex='0' className='modal-container__nav  modal-container__nav--right' onClick={this.handleNextClick}><i className='fa fa-fw fa-chevron-right' /></div>;
     }
 
-    if (attachment.get('type') === 'image') {
-      content = media.map((image) => {
-        const width  = image.getIn(['meta', 'original', 'width']) || null;
-        const height = image.getIn(['meta', 'original', 'height']) || null;
+    content = media.map((image) => {
+      const width  = image.getIn(['meta', 'original', 'width']) || null;
+      const height = image.getIn(['meta', 'original', 'height']) || null;
 
+      if (image.get('type') === 'image') {
         return <ImageLoader previewSrc={image.get('preview_url')} src={image.get('url')} width={width} height={height} key={image.get('preview_url')} />;
-      }).toArray();
-    } else if (attachment.get('type') === 'gifv') {
-      content = <ExtendedVideoPlayer src={url} muted controls={false} />;
-    }
+      } else if (image.get('type') === 'gifv') {
+        return <ExtendedVideoPlayer src={image.get('url')} muted controls={false} width={width} height={height} key={image.get('preview_url')} />;
+      }
+
+      return null;
+    }).toArray();
 
     return (
       <div className='modal-root__modal media-modal'>
diff --git a/app/javascript/styles/components.scss b/app/javascript/styles/components.scss
index 02602afa4f7..bcf7ba4e017 100644
--- a/app/javascript/styles/components.scss
+++ b/app/javascript/styles/components.scss
@@ -2957,6 +2957,7 @@ button.icon-button.active i.fa-retweet {
   max-height: 80vh;
   position: relative;
 
+  .extended-video-player,
   img,
   canvas,
   video {
@@ -2966,6 +2967,13 @@ button.icon-button.active i.fa-retweet {
     height: auto;
   }
 
+  .extended-video-player,
+  video {
+    display: flex;
+    width: 80vw;
+    height: 80vh;
+  }
+
   img,
   canvas {
     display: block;