1 files changed, 6 insertions, 0 deletions
diff --git a/activesupport/lib/active_support/core_ext/string/output_safety.rb b/activesupport/lib/active_support/core_ext/string/output_safety.rb
index 3bf4edbdef..6d6c4912bb 100644
--- a/activesupport/lib/active_support/core_ext/string/output_safety.rb
+++ b/activesupport/lib/active_support/core_ext/string/output_safety.rb
@@ -86,6 +86,12 @@ module ActiveSupport #:nodoc:
       end
     end
 
+    def[](*args)
+      new_safe_buffer = super
+      new_safe_buffer.instance_eval { @dirty = false }
+      new_safe_buffer
+    end
+
     def safe_concat(value)
       raise SafeConcatError if dirty?
       original_concat(value)