diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index 8daaec7ba..fed9e59e5 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1105,10 +1105,6 @@ Style/IfUnlessModifierOfIfUnless:
   Exclude:
     - 'app/models/attachment.rb'
 
-Style/IfWithSemicolon:
-  Exclude:
-    - 'lib/redmine/wiki_formatting/textile/redcloth3.rb'
-
 # Cop supports --auto-correct.
 # Configuration parameters: InverseMethods, InverseBlocks.
 Style/InverseMethods:
diff --git a/lib/redmine/wiki_formatting/textile/redcloth3.rb b/lib/redmine/wiki_formatting/textile/redcloth3.rb
index 300afdc11..d68c3a264 100644
--- a/lib/redmine/wiki_formatting/textile/redcloth3.rb
+++ b/lib/redmine/wiki_formatting/textile/redcloth3.rb
@@ -739,7 +739,7 @@ class RedCloth3 < String
     SETEXT_RE = /\A(.+?)\n([=-])[=-]* *$/m
     def block_markdown_setext( text )
         if text =~ SETEXT_RE
-            tag = if $2 == "="; "h1"; else; "h2"; end
+            tag = ($2 == "=" ? "h1" : "h2")
             blk, cont = "<#{ tag }>#{ $1 }</#{ tag }>", $'
             blocks cont
             text.replace( blk + cont )