diff --git a/Userland/Libraries/LibWeb/HTML/AttributeNames.h b/Userland/Libraries/LibWeb/HTML/AttributeNames.h
index ab609ee5ba1..88d83e94d81 100644
--- a/Userland/Libraries/LibWeb/HTML/AttributeNames.h
+++ b/Userland/Libraries/LibWeb/HTML/AttributeNames.h
@@ -39,6 +39,7 @@ namespace AttributeNames {
     __ENUMERATE_HTML_ATTRIBUTE(checked)                    \
     __ENUMERATE_HTML_ATTRIBUTE(cite)                       \
     __ENUMERATE_HTML_ATTRIBUTE(class_)                     \
+    __ENUMERATE_HTML_ATTRIBUTE(classid)                    \
     __ENUMERATE_HTML_ATTRIBUTE(clear)                      \
     __ENUMERATE_HTML_ATTRIBUTE(code)                       \
     __ENUMERATE_HTML_ATTRIBUTE(codetype)                   \
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLObjectElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLObjectElement.cpp
index e85b42c5aa8..cfdc8dcfbf0 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLObjectElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLObjectElement.cpp
@@ -36,8 +36,21 @@ void HTMLObjectElement::parse_attribute(FlyString const& name, DeprecatedString
 {
     BrowsingContextContainer::parse_attribute(name, value);
 
-    if (name == HTML::AttributeNames::data)
+    // https://html.spec.whatwg.org/multipage/iframe-embed-object.html#the-object-element
+    // Whenever one of the following conditions occur:
+    if (
+        // - the element's classid attribute is set, changed, or removed,
+        (name == HTML::AttributeNames::classid) ||
+        // - the element's classid attribute is not present, and its data attribute is set, changed, or removed,
+        (!has_attribute(HTML::AttributeNames::classid) && name == HTML::AttributeNames::data) ||
+        // - neither the element's classid attribute nor its data attribute are present, and its type attribute is set, changed, or removed,
+        (!has_attribute(HTML::AttributeNames::classid) && !has_attribute(HTML::AttributeNames::data) && name == HTML::AttributeNames::type)) {
+
+        // ...the user agent must queue an element task on the DOM manipulation task source given
+        // the object element to run the following steps to (re)determine what the object element represents.
+        // This task being queued or actively running must delay the load event of the element's node document.
         queue_element_task_to_run_object_representation_steps();
+    }
 }
 
 // https://html.spec.whatwg.org/multipage/iframe-embed-object.html#attr-object-data