diff --git a/plugin.rb b/plugin.rb
index de44ccc..f95d803 100644
--- a/plugin.rb
+++ b/plugin.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # name: allowList
 # about: Whitelist a some custom CSS classes for div, span for typography experiments
 # version: 0.3