; Improve documentation of 'string-glyph-split'

* doc/lispref/display.texi (Size of Displayed Text):
* lisp/emacs-lisp/subr-x.el (string-glyph-split): Document a
caveat (bug#79576).

1 files changed, 4 insertions, 0 deletions

diff --git a/doc/lispref/display.texi b/doc/lispref/display.texi
index f363b044203..6abbefff7a5 100644
--- a/doc/lispref/display.texi
+++ b/doc/lispref/display.texi
@@ -2459,6 +2459,10 @@ you can say:
 @example
 (apply #'insert (cdr (string-glyph-split string))))
 @end example
+
+Caveat: for this function to recognize and process character
+compositions, @code{auto-composition-mode} must be enabled, and the
+current buffer must be displayed in some window.
 @end defun
 
 When a buffer is displayed with line numbers (@pxref{Display Custom,,,