emacs-29 40c23c11e8: * lisp/outline.el: Fix the value 'insert' of outline-minor-mode-use-buttons.

[Juri Linkov]

branch: emacs-29
commit 40c23c11e884bd14c9340a4853ab5db02901fe65
Author: Juri Linkov <juri@linkov.net>
Commit: Juri Linkov <juri@linkov.net>

    * lisp/outline.el: Fix the value 'insert' of outline-minor-mode-use-buttons.
    
    (outline--insert-button): Keep text properties around point
    on the inserted whitespace placeholder.
    
    * lisp/apropos.el (apropos-mode):
    * lisp/progmodes/xref.el (xref--xref-buffer-mode):
    Change outline-minor-mode-use-buttons from t to 'insert'.
---
 lisp/apropos.el        | 2 +-
 lisp/outline.el        | 2 +-
 lisp/progmodes/xref.el | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lisp/apropos.el b/lisp/apropos.el
index a731926f45..89f1f150a1 100644
--- a/lisp/apropos.el
+++ b/lisp/apropos.el
@@ -496,7 +496,7 @@ Intended as a value for `revert-buffer-function'."
               outline-level (lambda () 1)
               outline-minor-mode-cycle t
               outline-minor-mode-highlight t
-              outline-minor-mode-use-buttons t))
+              outline-minor-mode-use-buttons 'insert))
 
 (defvar apropos-multi-type t
   "If non-nil, this apropos query concerns multiple types.
diff --git a/lisp/outline.el b/lisp/outline.el
index 2c3f9798ec..53bfc4d556 100644
--- a/lisp/outline.el
+++ b/lisp/outline.el
@@ -1817,7 +1817,7 @@ With a prefix argument, show headings up to that LEVEL."
         (unless o
           (when (eq outline-minor-mode-use-buttons 'insert)
             (let ((inhibit-read-only t))
-              (insert "  ")
+              (insert (apply #'propertize "  " (text-properties-at (point))))
               (beginning-of-line)))
           (setq o (make-overlay (point) (1+ (point))))
           (overlay-put o 'outline-button t)
diff --git a/lisp/progmodes/xref.el b/lisp/progmodes/xref.el
index 1e4aa4eba5..0790d3a565 100644
--- a/lisp/progmodes/xref.el
+++ b/lisp/progmodes/xref.el
@@ -994,7 +994,7 @@ point."
   (setq-local add-log-current-defun-function
              #'xref--add-log-current-defun)
   (setq-local outline-minor-mode-cycle t
-              outline-minor-mode-use-buttons t
+              outline-minor-mode-use-buttons 'insert
               outline-search-function
               (lambda (&optional bound move backward looking-at)
                 (outline-search-text-property