From fdfe617e7378c9af5a294193eb7e204833227334 Mon Sep 17 00:00:00 2001
From: Tassilo Horn <tsdh@gnu.org>
Date: Tue, 17 Mar 2026 06:13:54 +0100
Subject: [PATCH] Further improve blink-matching-paren-highlight-offscreen

* lisp/simple.el (blink-matching-paren-offscreen): Inherit from
show-paren-match face.
(blink-paren-open-paren-line-string): Add blink-matching-paren-offscreen
face properties to opening paren instead of replacing original
fontification.
* lisp/paren.el (show-paren-context-when-offscreen): Mention
blink-matching-paren-highlight-offscreen in docstring.
---
 lisp/paren.el  |  5 ++++-
 lisp/simple.el | 23 +++++++----------------
 2 files changed, 11 insertions(+), 17 deletions(-)

diff --git a/lisp/paren.el b/lisp/paren.el
index 0a2e47e66a6..1ab3f9a32cf 100644
--- a/lisp/paren.el
+++ b/lisp/paren.el
@@ -103,7 +103,10 @@ If set to the symbol `child-frame', the context is shown in a
 child frame at the top-left of the window.  You might want to
 customize the `child-frame-border' face (especially the
 background color) to give the child frame a distinguished border.
-On non-graphical frames, the context is shown in the echo area."
+On non-graphical frames, the context is shown in the echo area.
+
+Note that `blink-matching-paren-highlight-offscreen' can have an
+influence on the fontification of the opening offscreen paren."
   :type '(choice (const :tag "Off" nil)
                  (const :tag "In echo area" t)
                  (const :tag "In overlay" overlay)
diff --git a/lisp/simple.el b/lisp/simple.el
index b6b729cd9c1..ff7ffafa3a1 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -9528,7 +9528,7 @@ This highlighting uses the `blink-matching-paren-offscreen' face."
   :group 'paren-blinking)
 
 (defface blink-matching-paren-offscreen
-  '((t :foreground "green"))
+  '((t :inherit show-paren-match))
   "Face for showing in the echo area matched open paren that is off-screen.
 This face is used only when `blink-matching-paren-highlight-offscreen'
 is non-nil."
@@ -9689,21 +9689,12 @@ face if `blink-matching-paren-highlight-offscreen' is non-nil."
               (lambda (region)
                 (buffer-substring (car region) (cdr region)))
               regions
-              "..."))
-            (openparen-next-char-idx (1+ openparen-idx)))
-        (concat
-         (substring line-string
-                    0 openparen-idx)
-         (let ((matched-offscreen-openparen
-                (substring line-string
-                           openparen-idx openparen-next-char-idx)))
-           (if blink-matching-paren-highlight-offscreen
-               (propertize
-                (substring-no-properties matched-offscreen-openparen)
-                'face 'blink-matching-paren-offscreen)
-             matched-offscreen-openparen))
-         (substring line-string
-                    openparen-next-char-idx))))))
+              "...")))
+        (when blink-matching-paren-highlight-offscreen
+          (add-face-text-property openparen-idx (1+ openparen-idx)
+                                  'blink-matching-paren-offscreen
+                                  nil line-string))
+        line-string))))
 
 (defvar blink-paren-function 'blink-matching-open
   "Function called, if non-nil, whenever a close parenthesis is inserted.