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emacs.el

@@ -3101,11 +3101,28 @@ BEGIN {
 ")
 
 '(progn
+   ;; https://web.sfc.wide.ad.jp/~sagawa/gnujdoc/elisp-manual-20-2.5/elisp-ja_39.html#SEC629
+   ;; https://emacs.stackexchange.com/questions/15078/inserting-before-an-after-string-overlay
+   ;; https://emacs.stackexchange.com/questions/3030/temporary-text-in-window-location-with-no-text-to-propertize-overlay
+   ;; https://ayatakesi.github.io/lispref/26.3/html/Overlay-Properties.html
+   ;; https://ayatakesi.github.io/lispref/26.3/html/Special-Properties.html#Special-Properties
+   ;; https://ayatakesi.github.io/lispref/28.1/html/Attribute-Functions.html
+   ;; https://ayatakesi.github.io/lispref/26.3/html/Display-Margins.html#Display-Margins
    (setq my-ov (make-overlay (pos-bol) (pos-eol)))
-   (let ((ov my-ov)
-         (s (propertize " "
-                        'display
-                        '((margin right-margin) "*"))))
+   (defface my-ov-face () "Face for my-ov.")
+   (set-face-attribute 'my-ov-face
+                       nil
+                       :background nil)
+   (set-face-attribute 'my-ov-face
+                       nil
+                       :foreground "yellow")
+   (let* ((ov my-ov)
+          (s (propertize "<"
+                         'face
+                         'my-ov-face))
+          (s (propertize " "
+                         'display
+                         `((margin right-margin) ,s))))
      (overlay-put ov 'after-string s)
      ;; (overlay-put ov 'after-string
      ;;              (concat (propertize " " 'display