emacs-29 01e8a0c6cbf: Doc fix for prettify-symbols-unprettify-at-point

[Stefan Kangas]

branch: emacs-29
commit 01e8a0c6cbf38c80ceb43b099ae1624697048302
Author: Stefan Kangas <stefankangas@gmail.com>
Commit: Stefan Kangas <stefankangas@gmail.com>

    Doc fix for prettify-symbols-unprettify-at-point
    
    * lisp/progmodes/prog-mode.el
    (prettify-symbols-unprettify-at-point): Document that it has to be
    set before enabling 'prettify-symbols-mode'.  (Bug#65884)
---
 lisp/progmodes/prog-mode.el | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lisp/progmodes/prog-mode.el b/lisp/progmodes/prog-mode.el
index 0f3a477abe5..4d8246155e9 100644
--- a/lisp/progmodes/prog-mode.el
+++ b/lisp/progmodes/prog-mode.el
@@ -216,7 +216,10 @@ If set to the symbol `right-edge', also unprettify if point
 is immediately after the symbol.  The prettification will be
 reapplied as soon as point moves away from the symbol.  If
 set to nil, the prettification persists even when point is
-on the symbol."
+on the symbol.
+
+This will only have an effect if it is set to a non-nil before
+`prettify-symbols-mode' is activated."
   :version "25.1"
   :type '(choice (const :tag "Never unprettify" nil)
                  (const :tag "Unprettify when point is inside" t)