diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index 76389e563..0da5b7de1 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1453,7 +1453,6 @@ Style/WhileUntilModifier:
     - 'app/models/project.rb'
     - 'lib/redmine/unified_diff.rb'
     - 'lib/redmine/utils.rb'
-    - 'lib/redmine/wiki_formatting/textile/redcloth3.rb'
 
 # Cop supports --auto-correct.
 # Configuration parameters: EnforcedStyle, MinSize, WordRegex.
diff --git a/lib/redmine/wiki_formatting/textile/redcloth3.rb b/lib/redmine/wiki_formatting/textile/redcloth3.rb
index 5d7ac768b..750bf8cac 100644
--- a/lib/redmine/wiki_formatting/textile/redcloth3.rb
+++ b/lib/redmine/wiki_formatting/textile/redcloth3.rb
@@ -1022,9 +1022,9 @@ class RedCloth3 < String
     def flush_left( text )
         indt = 0
         if text =~ /^ /
-            while text !~ /^ {#{indt}}[^ ]/
-                indt += 1
-            end unless text.empty?
+            unless text.empty?
+                indt += 1 while text !~ /^ {#{indt}}[^ ]/
+            end
             if indt.nonzero?
                 text.gsub!( /^ {#{indt}}/, '' )
             end