diff --git a/NEWS b/NEWS
index 6c30ac60aa8..0ac58590334 100644
--- a/NEWS
+++ b/NEWS
@@ -60,6 +60,7 @@ PHP                                                                        NEWS
 
 - Tidy:
   . Fix memory leak in tidy output handler on error. (nielsdos)
+  . Fix tidyOptIsReadonly deprecation, using tidyOptGetCategory. (David Carlier)
 
 06 Jun 2025, PHP 8.4.8
 
diff --git a/ext/tidy/config.m4 b/ext/tidy/config.m4
index 8c3ceb38daf..bb852363465 100644
--- a/ext/tidy/config.m4
+++ b/ext/tidy/config.m4
@@ -57,6 +57,12 @@ if test "$PHP_TIDY" != "no"; then
     [],
     [-L$TIDY_LIBDIR])
 
+  PHP_CHECK_LIBRARY([$TIDY_LIB_NAME], [tidyOptGetCategory],
+    [AC_DEFINE([HAVE_TIDYOPTGETCATEGORY], [1],
+      [Define to 1 if Tidy library has the 'tidyOptGetCategory' function.])],
+    [],
+    [-L$TIDY_LIBDIR])
+
   PHP_ADD_LIBRARY_WITH_PATH([$TIDY_LIB_NAME],
     [$TIDY_LIBDIR],
     [TIDY_SHARED_LIBADD])
diff --git a/ext/tidy/tidy.c b/ext/tidy/tidy.c
index 351002c6dd5..ab991b2f8b7 100644
--- a/ext/tidy/tidy.c
+++ b/ext/tidy/tidy.c
@@ -234,7 +234,11 @@ static int _php_tidy_set_tidy_opt(TidyDoc doc, const char *optname, zval *value)
 		return FAILURE;
 	}
 
+#if defined(HAVE_TIDYOPTGETCATEGORY)
+	if (tidyOptGetCategory(opt) == TidyInternalCategory) {
+#else
 	if (tidyOptIsReadOnly(opt)) {
+#endif
 		php_error_docref(NULL, E_WARNING, "Attempting to set read-only option \"%s\"", optname);
 		return FAILURE;
 	}