Take another crack at making sure WAYLAND_DISPLAY is set

init.el

@@ -703,6 +703,28 @@ in the region and indents once)."
       (funcall oldfun type)))
   (advice-add 'xclip-get-selection :around 'my/-xclip-detect-wl-paste-error))
 
+;; Set the WAYLAND_DISPLAY environment variable
+(require 'xdg)
+(defun my/detect-wayland-display ()
+  "Try to set the WAYLAND_DISPLAY environment variable.
+This attempts to detect a running Wayland session and set the WAYLAND_DISPLAY
+environment variable accordingly."
+  (let ((found '(nil . nil)))
+    (dolist (entry (directory-files-and-attributes
+                    (xdg-runtime-dir) nil nil 'nosort)
+                   (cdr found))
+      (cl-destructuring-bind (name . attrs) entry
+        (when-let (((string-match (rx bos "wayland-" (group (+ (any "0-9"))) eos)
+                                  name))
+                   (id (string-to-number (match-string 1 name)))
+                   ((or (not (car found)) (< id (car found))))
+
+                   ;; socket
+                   ((string-prefix-p "s" (file-attribute-modes attrs))))
+          (setq found (cons id name)))))))
+(unless (getenv "WAYLAND_DISPLAY")
+  (setenv "WAYLAND_DISPLAY" (my/detect-wayland-display)))
+
 ;; which-key
 (use-package which-key
   :diminish which-key-mode