added loading indicator

frontend/js/videos.js

@@ -134,6 +134,9 @@ App.videos = App.videos || {};
                     <button class="video-menu-item" type="button" data-action="download" role="menuitem">Download</button>
                 </div>
                 <img src="${v.thumb}" alt="${v.title}">
+                <div class="video-loading" aria-hidden="true">
+                    <div class="video-loading-spinner"></div>
+                </div>
                 <h4>${v.title}</h4>
                 ${uploaderText ? `<p class="video-meta"><button class="uploader-link" type="button" data-uploader="${uploaderText}">${uploaderText}</button></p>` : ''}
                 ${durationText ? `<p class="video-duration">${durationText}</p>` : ''}
@@ -183,7 +186,11 @@ App.videos = App.videos || {};
                     App.videos.closeAllMenus();
                 };
             }
-            card.onclick = () => App.player.open(v);
+            card.onclick = () => {
+                if (card.classList.contains('is-loading')) return;
+                card.classList.add('is-loading');
+                App.player.open(v, { originEl: card });
+            };
             grid.appendChild(card);
             state.renderedVideoIds.add(v.id);
         });