class attributes must inherit or we break Pro UI extensions

Changes.md

@@ -5,6 +5,9 @@ HEAD
 
 - Allow disabling of Sidekiq::Web's cookie session to handle the
   case where the app provides a session already [#3180]
+```ruby
+Sidekiq::Web.set :sessions, false
+```
 - Fix Web UI sharding support broken in 4.2.2. [#3169]
 - Relax rack-protection version to >= 1.5.0
 

lib/sidekiq/web.rb

@@ -80,6 +80,13 @@ module Sidekiq
       attr_writer :locales, :views
     end
 
+    def self.inherited(child)
+      child.app_url = self.app_url
+      child.session_secret = self.session_secret
+      child.redis_pool = self.redis_pool
+      child.sessions = self.sessions
+    end
+
     def settings
       self.class.settings
     end