diff --git a/lisp/simple.el b/lisp/simple.el
index 44aa26eb0d0..b0669d674ee 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -9691,7 +9691,6 @@ face if `blink-matching-paren-highlight-offscreen' is non-nil."
               regions
               "..."))
             (openparen-next-char-idx (1+ openparen-idx)))
-        (setq line-string (substring-no-properties line-string))
         (concat
          (substring line-string
                     0 openparen-idx)
@@ -9699,8 +9698,9 @@ face if `blink-matching-paren-highlight-offscreen' is non-nil."
                 (substring line-string
                            openparen-idx openparen-next-char-idx)))
            (if blink-matching-paren-highlight-offscreen
-               (propertize matched-offscreen-openparen
-                           'face 'blink-matching-paren-offscreen)
+               (propertize
+                (substring-no-properties matched-offscreen-openparen)
+                'face 'blink-matching-paren-offscreen)
              matched-offscreen-openparen))
          (substring line-string
                     openparen-next-char-idx))))))