Add mixes to genre channels

src/invidious.cr

@@ -2471,7 +2471,14 @@ get "/channel/:ucid" do |env|
     sort_by ||= "last"
 
     items, continuation = fetch_channel_playlists(ucid, author, auto_generated, continuation, sort_by)
-    items.select! { |item| item.is_a?(SearchPlaylist) && !item.videos.empty? }
+    items.uniq! do |item|
+      if item.responds_to?(:title)
+        item.title
+      elsif item.responds_to?(:author)
+        item.author
+      end
+    end
+    items.select! { |item| item.responds_to?(:thumbnail_id) && item.thumbnail_id }
     items = items.map { |item| item.as(SearchPlaylist) }
     items.each { |item| item.author = "" }
   else

src/invidious/helpers/helpers.cr

@@ -416,12 +416,18 @@ def extract_shelf_items(nodeset, ucid = nil, author_name = nil)
           thumbnail_id = playlist_thumbnail.match(/\/vi\/(?<video_id>[a-zA-Z0-9_-]{11})\/\w+\.jpg/).try &.["video_id"]
         end
 
+        video_count_label = child_node.xpath_node(%q(.//span[@class="formatted-video-count-label"]))
+        if video_count_label
+          video_count = video_count_label.content.strip.match(/^\d+/).try &.[0].to_i?
+        end
+        video_count ||= 50
+
         items << SearchPlaylist.new(
           playlist_title,
           plid,
           author_name,
           ucid,
-          50,
+          video_count,
           Array(SearchPlaylistVideo).new,
           thumbnail_id
         )