diff --git a/config/initializers/content_security_policy.rb b/config/initializers/content_security_policy.rb
new file mode 100644
index 00000000..ab00184c
--- /dev/null
+++ b/config/initializers/content_security_policy.rb
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+# License: AGPL-3.0-or-later WITH Web-Template-Output-Additional-Permission-3.0-or-later
+Rails.application.config.content_security_policy do |policy|
+    policy.connect_src :self, :https, "http://localhost:3035", "ws://localhost:3035" if Rails.env.development?
+end
\ No newline at end of file