diff --git a/config/initializers/web_app_manifest.rb b/config/initializers/web_app_manifest.rb
index bfae462d..e0b54d66 100644
--- a/config/initializers/web_app_manifest.rb
+++ b/config/initializers/web_app_manifest.rb
@@ -6,6 +6,16 @@
 # to asset_path in the _favicon.html.erb partial.
 
 Rails.application.config.assets.configure do |env|
+  mime_type = 'application/manifest+json'
+  extensions = ['.webmanifest']
+
+  if Sprockets::VERSION.to_i >= 4
+    extensions << '.webmanifest.erb'
+    env.register_preprocessor(mime_type, Sprockets::ERBProcessor)
+  end
+
+  env.register_mime_type(mime_type, extensions: extensions)
+
   # Register .webmanifest files with the correct MIME type
-  env.register_mime_type 'application/manifest+json', extensions: ['.webmanifest']
+  # env.register_mime_type 'application/manifest+json', extensions: ['.webmanifest']
 end