diff --git a/README.org b/README.org
index f750680..da9c249 100644
--- a/README.org
+++ b/README.org
@@ -4961,7 +4961,8 @@ Listing [[lst:bug-reference-mode]] configures ~bug-reference-mode~ for use with
 (ensure-package-installation 'debbugs)
 (defvar bug-reference-url-format
   "https://debbugs.gnu.org/cgi/bugreport.cgi?bug=%s"
-  "Setting this as a file local variable enables `bug-reference-mode'")
+  "Format to use `gnu-debbugs' URL.")
+(put 'bug-reference-mode 'safe-local-variable 'booleanp))
 #+end_src
 
 *** [[info:elisp#Debugging][Debugging Emacs Lisp (info)]]
@@ -6402,7 +6403,7 @@ Only the [[info:org#Top][Org]] source file shows the local variables footer.
 # Emacs looks for "Local variables:" after the last "newline-formfeed".
 
 # Local Variables:
-# bug-reference-url-format: "https://debbugs.gnu.org/cgi/bugreport.cgi?bug=%s"
+# bug-reference-mode: t
 # compile-command: "latexmk -interaction=nonstopmode -lualatex -pvc -shell-escape README.tex"
 # fill-column: 80
 # org-edit-src-content-indentation: 0