doc: Document which-key deferral bug

users/crumb/programs/emacs/modules/syd-keybinds.el

@@ -69,6 +69,8 @@ are active.")
 
 ;; Show possible completions for a partially-entered key sequence.
 (use-package which-key
+  ;; BUG: (#4) If the first input is a prefix key, `which-key-mode' won't be
+  ;; activated in time.
   :hook (on-first-input . which-key-mode)
   :custom ((which-key-allow-evil-operators t)
            (which-key-show-operator-state-maps t)))