message-valid-fqdn-regexp no longer exists

* lisp/gnus/gnus-art.el (gnus-button-valid-fqdn-regexp): Don't use
the no-longer-existing message-valid-fqdn-regexp variable.

diff --git a/lisp/gnus/gnus-art.el b/lisp/gnus/gnus-art.el
index 366d14aca1d026f27cd313a852f89eeb7f3c8003..e9c2921a413f6eaa959fd604c8e36656e76300f2 100644 (file)
--- a/lisp/gnus/gnus-art.el
+++ b/lisp/gnus/gnus-art.el
@@ -7452,10 +7452,9 @@ groups."
   :group 'gnus-article-buttons
   :type 'regexp)
 
-(defcustom gnus-button-valid-fqdn-regexp
-  message-valid-fqdn-regexp
+(defcustom gnus-button-valid-fqdn-regexp "\\([-A-Za-z0-9]+\\.\\a)+[A-Za-z]+"
   "Regular expression that matches a valid FQDN."
-  :version "22.1"
+  :version "25.2"
   :group 'gnus-article-buttons
   :type 'regexp)