diff --git a/railties/lib/rails/backtrace_cleaner.rb b/railties/lib/rails/backtrace_cleaner.rb
index 485ab3e1c2..adf23556ee 100644
--- a/railties/lib/rails/backtrace_cleaner.rb
+++ b/railties/lib/rails/backtrace_cleaner.rb
@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require "active_support/backtrace_cleaner"
+require "active_support/core_ext/string/access"
 
 module Rails
   class BacktraceCleaner < ActiveSupport::BacktraceCleaner