proxify HLS by its host header

src/invidious/routes/api/manifest.cr

@@ -224,7 +224,7 @@ module Invidious::Routes::API::Manifest
         if !proxy.empty?
           "#{proxy}/videoplayback?#{raw_params}"
         else
-          "#{HOST_URL}/videoplayback?#{raw_params}"
+          "#{env.request.headers["Host"]}/videoplayback?#{raw_params}"
         end
       end
     end
@@ -248,7 +248,7 @@ module Invidious::Routes::API::Manifest
     manifest = response.body
 
     if local
-      manifest = manifest.gsub("https://www.youtube.com", HOST_URL)
+      manifest = manifest.gsub("https://www.youtube.com", env.request.headers["Host"])
       manifest = manifest.gsub("index.m3u8", "index.m3u8?local=true")
     end