diff --git a/symbol-tag.el b/symbol-tag.el
--- a/symbol-tag.el
+++ b/symbol-tag.el
@@ -179,28 +179,30 @@
       (let ((i (string-match-p (concat "\\(?:" (or regexp "[ \t\n\r]+") "\\)\\'")
                                string)))
         (if i (substring string 0 i) string))))
-  (condition-case err
-      (progn
-        (require 'map)
-        (defalias 'unorg-x-plist-delete 'map-delete))
-    (error
-     (defun unorg-x-plist-delete (map key)
-       "Imported `map--plist-delete' from map.el.
+  (ignore-errors (require 'help-fns))
+  (unless (fboundp #'help--symbol-completion-table)
+    (defun help--symbol-completion-table (&rest args)))
+  (ignore-errors
+    (require 'map)
+    (defalias 'unorg-x-plist-delete 'map-delete))
+  (unless (fboundp #'unorg-x-plist-delete)
+    (defun unorg-x-plist-delete (map key)
+      "Imported `map--plist-delete' from map.el.
 Only available for Emacs 26."
-       (let ((tail map) last)
-         (while (consp tail)
-           (cond
-            ((not (equal key (car tail)))
-             (setq last tail)
-             (setq tail (cddr last)))
-            (last
-             (setq tail (cddr tail))
-             (setf (cddr last) tail))
-            (t
-             (cl-assert (eq tail map))
-             (setq map (cddr map))
-             (setq tail map))))
-         map))))
+      (let ((tail map) last)
+        (while (consp tail)
+          (cond
+           ((not (equal key (car tail)))
+            (setq last tail)
+            (setq tail (cddr last)))
+           (last
+            (setq tail (cddr tail))
+            (setf (cddr last) tail))
+           (t
+            (cl-assert (eq tail map))
+            (setq map (cddr map))
+            (setq tail map))))
+        map)))
   (unless (boundp 'occur-buffer)
     (defvar occur-buffer nil)))
 
@@ -787,6 +789,99 @@ comments, e.g.:
     (concat "\n" (symbol-tag-pp-to-string def t))))
 ;; (insert (symbol-tag-redef-vars (quote (dired-re-mark dired-re-sym))))
 
+(defvar wsk-kill-on-quit-prev-buffer nil
+  "Buffer to return to after quitting.")
+(make-variable-buffer-local 'wsk-kill-on-quit-prev-buffer)
+
+(defvar wsk-kill-on-quit-no-kill nil
+  "Do not kill buffer after quitting it not nil.
+Just bury it alive.")
+(make-variable-buffer-local 'wsk-kill-on-quit-no-kill)
+
+(defvar wsx-kill-on-quit-mode-map nil
+  "|:todo:| doc.")
+(unless wsx-kill-on-quit-mode-map
+  (define-prefix-command 'wsx-kill-on-quit-mode-map nil "koq"))
+
+(defun wsx-kill-on-quit ()
+  "|:todo:| doc."
+  (interactive)
+  (let ((to-be-killed (current-buffer))
+        (prev-buffer wsk-kill-on-quit-prev-buffer)
+        (no-kill wsk-kill-on-quit-no-kill))
+    (if no-kill (bury-buffer) (kill-buffer))
+    (if prev-buffer (select-window (get-buffer-window prev-buffer)))))
+
+(define-key wsx-kill-on-quit-mode-map [?\C-c ?\C-c] 'wsx-kill-on-quit)
+
+;;;###autoload
+(define-minor-mode wsx-kill-on-quit-minor-mode
+  "Minor mode for killing temporary buffer when quitting.
+
+The following keys are defined when
+`wsx-kill-on-quit-minor-mode' is activated with
+`\\[wsx-kill-on-quit-minor-mode]':
+
+\\{wsx-kill-on-quit-mode-map}"
+  :group 'workspace
+  :lighter " koq"
+  :global nil
+  :keymap wsx-kill-on-quit-mode-map
+  (cond
+   (wsx-kill-on-quit-minor-mode
+    ;; Turned on.
+    )
+   (t
+    ;; Turned off.
+    )))
+;; (wsx-kill-on-quit-minor-mode)
+
+;;;###autoload
+(defun symbol-tag-redefine (variable)
+  "Redefine VARIABLE in temporary buffer."
+  (interactive
+   (let ((v (variable-at-point))
+         (enable-recursive-minibuffers t)
+         (orig-buffer (current-buffer))
+         val)
+     (setq val (completing-read
+                (if (symbolp v)
+                    (format
+                     "Redefine variable (default %s): " v)
+                  "Redefine variable: ")
+                #'help--symbol-completion-table
+                (lambda (vv)
+                  (with-current-buffer orig-buffer
+                    (or (get vv 'variable-documentation)
+                        (and (boundp vv) (not (keywordp vv))))))
+                t nil nil
+                (if (symbolp v) (symbol-name v))))
+     (list (if (equal val "")
+               v (intern val)))))
+    (if (not (symbolp variable))
+        (error "You did not specify a variable"))
+    (let ((orig-buffer (current-buffer))
+          (buffer (format "*redefine %s*" variable))
+          output-buffer)
+      (with-output-to-temp-buffer buffer
+        (princ
+         (substring
+          (symbol-tag-redef-vars (list variable)) 1)))
+      (setq output-buffer (get-buffer buffer))
+      (select-window (get-buffer-window output-buffer))
+      (read-only-mode 0)
+      (goto-char (point-min))
+      (unless (looking-at "^;;")
+        (insert ";; `C-c C-c' to quit\n"))
+      (emacs-lisp-mode)
+      (wsx-kill-on-quit-minor-mode 1)
+      ;; (setq wsk-kill-on-quit-no-kill t)
+      (setq wsk-kill-on-quit-prev-buffer orig-buffer)
+      (ignore-errors
+        (down-list 2)
+        (forward-sexp 3)
+        (forward-sexp -1))))
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; :doc: Variables - Mode                                        :var:
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -929,9 +1024,11 @@ Use the following expression to insert a
    )
  "Symbol tag delimiter stack.
 
-Use the following expression to insert a valid expression to
-redefine all dlm stack variables:
-;; (insert (symbol-tag-redef-vars (quote (symbol-tag-dlm-default symbol-tag-dlm-stack-default symbol-tag-dlm symbol-tag-dlm-stack))))")
+Use the following expression to redefine:
+;; (insert (symbol-tag-redef-vars (quote (symbol-tag-dlm-stack-default))))
+
+Use the following expression to redefine all dlm stack variables:
+;; (symbol-tag-dlm-redefine)")
 
 ;;;###autoload
 (defvar symbol-tag-dlm