diff --git c/lisp/gnus/gnus-srvr.el i/lisp/gnus/gnus-srvr.el
index a520bfcd8b..54be0f8e6a 100644
--- c/lisp/gnus/gnus-srvr.el
+++ i/lisp/gnus/gnus-srvr.el
@@ -699,7 +699,6 @@ gnus-browse-mode-map
   "n" #'gnus-browse-next-group
   "p" #'gnus-browse-prev-group
   "DEL" #'gnus-browse-prev-group
-  "<delete>" #'gnus-browse-prev-group
   "N" #'gnus-browse-next-group
   "P" #'gnus-browse-prev-group
   "M-n" #'gnus-browse-next-group
diff --git c/lisp/gnus/gnus-sum.el i/lisp/gnus/gnus-sum.el
index bf2a083fec..90b57695c5 100644
--- c/lisp/gnus/gnus-sum.el
+++ i/lisp/gnus/gnus-sum.el
@@ -1958,8 +1958,6 @@ :keymap
   "C-M-b" #'gnus-summary-prev-thread
   "M-<down>" #'gnus-summary-next-thread
   "M-<up>" #'gnus-summary-prev-thread
-  "C-M-u" #'gnus-summary-up-thread
-  "C-M-d" #'gnus-summary-down-thread
   "&" #'gnus-summary-execute-command
   "c" #'gnus-summary-catchup-and-exit
   "C-w" #'gnus-summary-mark-region-as-read
diff --git c/lisp/ibuffer.el i/lisp/ibuffer.el
index 742d21d0b0..65430d7d11 100644
--- c/lisp/ibuffer.el
+++ i/lisp/ibuffer.el
@@ -447,7 +447,6 @@ ibuffer-mode-map
 
   "d"           #'ibuffer-mark-for-delete
   "C-d"         #'ibuffer-mark-for-delete-backwards
-  "k"           #'ibuffer-mark-for-delete
   "x"           #'ibuffer-do-kill-on-deletion-marks
 
   ;; immediate operations
diff --git c/lisp/wdired.el i/lisp/wdired.el
index a5858ed190..106d57174d 100644
--- c/lisp/wdired.el
+++ i/lisp/wdired.el
@@ -902,7 +902,6 @@ wdired-perm-mode-map
   "x"   #'wdired-set-bit
   "-"   #'wdired-set-bit
   "S"   #'wdired-set-bit
-  "s"   #'wdired-set-bit
   "T"   #'wdired-set-bit
   "t"   #'wdired-set-bit
   "s"   #'wdired-set-bit