Fix

app/models/communication/block/template/video.rb

@@ -5,7 +5,12 @@ class Communication::Block::Template::Video < Communication::Block::Template::Ba
   has_component :transcription, :text
 
   def video_iframe
-    video_provider.iframe_tag(title: video_title)
+    video_provider.iframe_tag(title: video_iframe_title)
+  end
+
+  def video_iframe_title
+    video_title.blank?  ? 'Video'
+                        : video_title
   end
 
   def video_platform

app/services/video/provider/default.rb

@@ -51,7 +51,7 @@ class Video::Provider::Default
 
   def default_iframe_options
     {
-      class: (platform == :default ? nil : platform),
+      class: platform,
       loading: 'lazy',
       src: iframe_url
     }