** Keyboard problems
+*** PGTK build of Emacs running on Wayland doesn't recognize Hyper modifier
+
+If you arrange for the Wayland compositor to send the Hyper key
+modifier (e.g., via XKB customizations), the Hyper modifier will still
+not be reported to Emacs.
+
+The reason is that GDK 3.x doesn't recognize the Hyper key modifier.
+Since GDK 3.x is no longer developed, this bug in GDK will probably
+never be solved. And the Emacs PGTK build cannot yet support GTK4,
+where this problem is reportedly solved.
+
*** Unable to enter the M-| key on some German keyboards.
Some users have reported that M-| suffers from "keyboard ghosting".
This can't be fixed by Emacs, as the keypress never gets passed to it
future, upgrade to a newer version which solves the problem, when such
a fixed version becomes available).
+*** Emacs running on WSL receives stray characters as input.
+
+For example, you could see Emacs inserting 'z' characters even though
+nothing is typed on the keyboard, and even if you unplug the keyboard.
+
+The reason is a bug in the WSL X server's handling of key-press and
+key-repeat events. A workaround is to use the Cygwin or native
+MS-Windows build of Emacs instead.
+
** Problems with hostname resolution
*** Emacs does not know your host's fully-qualified domain name.