diff --git a/src-ui/src/app/components/document-detail/document-detail.component.html b/src-ui/src/app/components/document-detail/document-detail.component.html
index 8486e1816..677596d8f 100644
--- a/src-ui/src/app/components/document-detail/document-detail.component.html
+++ b/src-ui/src/app/components/document-detail/document-detail.component.html
@@ -364,7 +364,7 @@
             </pdf-viewer>
           </div>
         } @else {
-          <object [data]="previewUrl | safeUrl" class="preview-sticky" width="100%"></object>
+          <object [data]="previewUrl | safeUrl" type="application/pdf" class="preview-sticky" width="100%"></object>
         }
       }
       @case (ContentRenderType.Text) {