diff --git a/runtime/compiler/pandoc.vim b/runtime/compiler/pandoc.vim
index 5d90a518c9..40d2d02633 100644
--- a/runtime/compiler/pandoc.vim
+++ b/runtime/compiler/pandoc.vim
@@ -2,6 +2,7 @@
 " Compiler:     Pandoc
 " Maintainer:   Konfekt
 " Last Change:	2024 Nov 19
+" 2025 May 15 Update the title regex for CompilerSet #17321
 "
 " Expects output file extension, say `:make html` or `:make pdf`.
 " Passes additional arguments to pandoc, say `:make html --self-contained`.
@@ -51,7 +52,7 @@ endfunction
 
 execute 'CompilerSet makeprg=pandoc'..escape(
     \ ' --standalone'..
-    \ (s:PandocFiletype(&filetype) ==# 'markdown' && (getline(1) =~# '^%\s\+\S\+' || (search('^title:\s+\S+', 'cnw') > 0)) ?
+    \ (s:PandocFiletype(&filetype) ==# 'markdown' && (getline(1) =~# '^%\s\+\S\+' || (search('^title:\s\+\S\+', 'cnw') > 0)) ?
     \ '' : ' --metadata title=%:t:r:S')..
     \ ' '..s:PandocLang()..
     \ ' --from='..s:PandocFiletype(&filetype)..