diff --git a/NEWS b/NEWS
index d25d441ca8b5..e4b665b80efa 100644
--- a/NEWS
+++ b/NEWS
@@ -15,6 +15,8 @@ PHP NEWS
that still have a live wrapper). (iliaal)
. Fixed a use-after-free when Dom\Element::setAttributeNS() replaces the
value of an attribute whose child still has a live wrapper. (iliaal)
+ . Dom\HTMLDocument::getElementById() now finds the ids of SVG and MathML
+ elements. (iliaal)
- GD:
. Fixed imageaffinematrixget() and imageaffinematrixconcat() reporting the
diff --git a/ext/dom/html5_parser.c b/ext/dom/html5_parser.c
index 34320a122f53..84a251c3687f 100644
--- a/ext/dom/html5_parser.c
+++ b/ext/dom/html5_parser.c
@@ -274,7 +274,7 @@ static lexbor_libxml2_bridge_status lexbor_libxml2_bridge_convert(
last_added_attr = lxml_attr;
/* xmlIsID does some other stuff too that is irrelevant here. */
- if (local_name_length == 2 && local_name[0] == 'i' && local_name[1] == 'd' && attr->node.ns == LXB_NS_HTML) {
+ if (local_name_length == 2 && local_name[0] == 'i' && local_name[1] == 'd' && (attr->node.ns == LXB_NS_HTML || attr->node.ns == LXB_NS_SVG || attr->node.ns == LXB_NS_MATH)) {
if (xmlAddID(NULL, lxml_doc, value, lxml_attr) == 0) {
/* If the ID already exists, the ID attribute still needs to be marked as an ID. */
lxml_attr->atype = XML_ATTRIBUTE_ID;
diff --git a/ext/dom/tests/modern/common/Document_getElementById_foreign_namespaces.phpt b/ext/dom/tests/modern/common/Document_getElementById_foreign_namespaces.phpt
new file mode 100644
index 000000000000..742d07a1345f
--- /dev/null
+++ b/ext/dom/tests/modern/common/Document_getElementById_foreign_namespaces.phpt
@@ -0,0 +1,23 @@
+--TEST--
+Dom\HTMLDocument::getElementById() finds ids of SVG and MathML elements
+--EXTENSIONS--
+dom
+--FILE--
+';
+$d = Dom\HTMLDocument::createFromString($html, LIBXML_NOERROR);
+var_dump([
+ 'svg #s' => $d->getElementById('s')?->tagName,
+ 'math #m' => $d->getElementById('m')?->tagName,
+ 'html #p' => $d->getElementById('p')?->tagName,
+]);
+?>
+--EXPECT--
+array(3) {
+ ["svg #s"]=>
+ string(3) "svg"
+ ["math #m"]=>
+ string(4) "math"
+ ["html #p"]=>
+ string(1) "P"
+}