diff --git a/Libraries/LibWeb/HTML/Navigable.cpp b/Libraries/LibWeb/HTML/Navigable.cpp
index d0949bfcc5c..fa42639b6b1 100644
--- a/Libraries/LibWeb/HTML/Navigable.cpp
+++ b/Libraries/LibWeb/HTML/Navigable.cpp
@@ -1327,7 +1327,8 @@ WebIDL::ExceptionOr<void> Navigable::populate_session_history_entry_document(
 // an optional serialized state-or-null navigationAPIState (default null),
 // an optional entry list or null formDataEntryList (default null),
 // an optional referrer policy referrerPolicy (default the empty string),
-// and an optional user navigation involvement userInvolvement (default "none"):
+// an optional user navigation involvement userInvolvement (default "none"),
+// and an optional Element sourceElement (default null):
 
 // https://html.spec.whatwg.org/multipage/browsing-the-web.html#navigate
 WebIDL::ExceptionOr<void> Navigable::navigate(NavigateParams params)
@@ -1346,6 +1347,7 @@ WebIDL::ExceptionOr<void> Navigable::navigate(NavigateParams params)
     auto const& form_data_entry_list = params.form_data_entry_list;
     auto referrer_policy = params.referrer_policy;
     auto user_involvement = params.user_involvement;
+    auto source_element = params.source_element;
     auto& active_document = *this->active_document();
     auto& realm = active_document.realm();
     auto& vm = this->vm();
@@ -1429,8 +1431,8 @@ WebIDL::ExceptionOr<void> Navigable::navigate(NavigateParams params)
         && !response
         && url.equals(active_session_history_entry()->url(), URL::ExcludeFragment::Yes)
         && url.fragment().has_value()) {
-        // 1. Navigate to a fragment given navigable, url, historyHandling, userInvolvement, navigationAPIState, and navigationId.
-        TRY(navigate_to_a_fragment(url, to_history_handling_behavior(history_handling), user_involvement, navigation_api_state, navigation_id));
+        // 1. Navigate to a fragment given navigable, url, historyHandling, userInvolvement, sourceElement, navigationAPIState, and navigationId.
+        TRY(navigate_to_a_fragment(url, to_history_handling_behavior(history_handling), user_involvement, source_element, navigation_api_state, navigation_id));
 
         // 2. Return.
         return {};
@@ -1492,7 +1494,8 @@ WebIDL::ExceptionOr<void> Navigable::navigate(NavigateParams params)
 
         // 4. Let continue be the result of firing a push/replace/reload navigate event at navigation
         //    with navigationType set to historyHandling, isSameDocument set to false, userInvolvement set to userInvolvement,
-        //    formDataEntryList set to entryListForFiring, destinationURL set to url, and navigationAPIState set to navigationAPIStateForFiring.
+        //    sourceElement set to sourceElement, formDataEntryList set to entryListForFiring, destinationURL set to url,
+        //    and navigationAPIState set to navigationAPIStateForFiring.
         auto navigation_type = [](Bindings::NavigationHistoryBehavior history_handling) {
             switch (history_handling) {
             case Bindings::NavigationHistoryBehavior::Push:
@@ -1504,7 +1507,7 @@ WebIDL::ExceptionOr<void> Navigable::navigate(NavigateParams params)
                 VERIFY_NOT_REACHED();
             }
         }(history_handling);
-        auto continue_ = navigation->fire_a_push_replace_reload_navigate_event(navigation_type, url, false, user_involvement, entry_list_for_firing, navigation_api_state_for_firing);
+        auto continue_ = navigation->fire_a_push_replace_reload_navigate_event(navigation_type, url, false, user_involvement, source_element, entry_list_for_firing, navigation_api_state_for_firing);
 
         // 5. If continue is false, then return.
         if (!continue_)
@@ -1611,7 +1614,7 @@ WebIDL::ExceptionOr<void> Navigable::navigate(NavigateParams params)
 }
 
 // https://html.spec.whatwg.org/multipage/browsing-the-web.html#navigate-fragid
-WebIDL::ExceptionOr<void> Navigable::navigate_to_a_fragment(URL::URL const& url, HistoryHandlingBehavior history_handling, UserNavigationInvolvement user_involvement, Optional<SerializationRecord> navigation_api_state, String navigation_id)
+WebIDL::ExceptionOr<void> Navigable::navigate_to_a_fragment(URL::URL const& url, HistoryHandlingBehavior history_handling, UserNavigationInvolvement user_involvement, GC::Ptr<DOM::Element> source_element, Optional<SerializationRecord> navigation_api_state, String navigation_id)
 {
     (void)navigation_id;
 
@@ -1623,10 +1626,11 @@ WebIDL::ExceptionOr<void> Navigable::navigate_to_a_fragment(URL::URL const& url,
     // 3. If navigationAPIState is not null, then set destinationNavigationAPIState to navigationAPIState.
     auto destination_navigation_api_state = navigation_api_state.has_value() ? *navigation_api_state : active_session_history_entry()->navigation_api_state();
 
-    // 4. Let continue be the result of firing a push/replace/reload navigate event at navigation with navigationType set to historyHandling, isSameDocument set to true,
-    //    userInvolvement set to userInvolvement, and destinationURL set to url, and navigationAPIState set to destinationNavigationAPIState.
+    // 4. Let continue be the result of firing a push/replace/reload navigate event at navigation with navigationType
+    //    set to historyHandling, isSameDocument set to true, userInvolvement set to userInvolvement, sourceElement set
+    //    to sourceElement, destinationURL set to url, and navigationAPIState set to destinationNavigationAPIState.
     auto navigation_type = history_handling == HistoryHandlingBehavior::Push ? Bindings::NavigationType::Push : Bindings::NavigationType::Replace;
-    bool const continue_ = navigation->fire_a_push_replace_reload_navigate_event(navigation_type, url, true, user_involvement, {}, destination_navigation_api_state);
+    bool const continue_ = navigation->fire_a_push_replace_reload_navigate_event(navigation_type, url, true, user_involvement, source_element, {}, destination_navigation_api_state);
 
     // 5. If continue is false, then return.
     if (!continue_)
diff --git a/Libraries/LibWeb/HTML/Navigable.h b/Libraries/LibWeb/HTML/Navigable.h
index 6b3052ac7ee..3fef494ce22 100644
--- a/Libraries/LibWeb/HTML/Navigable.h
+++ b/Libraries/LibWeb/HTML/Navigable.h
@@ -146,11 +146,12 @@ public:
         Optional<Vector<XHR::FormDataEntry>&> form_data_entry_list = {};
         ReferrerPolicy::ReferrerPolicy referrer_policy = ReferrerPolicy::ReferrerPolicy::EmptyString;
         UserNavigationInvolvement user_involvement = UserNavigationInvolvement::None;
+        GC::Ptr<DOM::Element> source_element = nullptr;
     };
 
     WebIDL::ExceptionOr<void> navigate(NavigateParams);
 
-    WebIDL::ExceptionOr<void> navigate_to_a_fragment(URL::URL const&, HistoryHandlingBehavior, UserNavigationInvolvement, Optional<SerializationRecord> navigation_api_state, String navigation_id);
+    WebIDL::ExceptionOr<void> navigate_to_a_fragment(URL::URL const&, HistoryHandlingBehavior, UserNavigationInvolvement, GC::Ptr<DOM::Element> source_element, Optional<SerializationRecord> navigation_api_state, String navigation_id);
 
     GC::Ptr<DOM::Document> evaluate_javascript_url(URL::URL const&, URL::Origin const& new_document_origin, UserNavigationInvolvement, String navigation_id);
     void navigate_to_a_javascript_url(URL::URL const&, HistoryHandlingBehavior, URL::Origin const& initiator_origin, UserNavigationInvolvement, CSPNavigationType csp_navigation_type, String navigation_id);
diff --git a/Libraries/LibWeb/HTML/NavigateEvent.cpp b/Libraries/LibWeb/HTML/NavigateEvent.cpp
index 05f9ee1b524..e14a05b001e 100644
--- a/Libraries/LibWeb/HTML/NavigateEvent.cpp
+++ b/Libraries/LibWeb/HTML/NavigateEvent.cpp
@@ -42,6 +42,7 @@ NavigateEvent::NavigateEvent(JS::Realm& realm, FlyString const& event_name, Navi
     , m_download_request(event_init.download_request)
     , m_info(event_init.info.value_or(JS::js_undefined()))
     , m_has_ua_visual_transition(event_init.has_ua_visual_transition)
+    , m_source_element(event_init.source_element)
 {
 }
 
@@ -62,6 +63,7 @@ void NavigateEvent::visit_edges(JS::Cell::Visitor& visitor)
     visitor.visit(m_signal);
     visitor.visit(m_form_data);
     visitor.visit(m_info);
+    visitor.visit(m_source_element);
 }
 
 // https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-navigateevent-intercept
diff --git a/Libraries/LibWeb/HTML/NavigateEvent.h b/Libraries/LibWeb/HTML/NavigateEvent.h
index 3b23533bbdb..2894c58a1c0 100644
--- a/Libraries/LibWeb/HTML/NavigateEvent.h
+++ b/Libraries/LibWeb/HTML/NavigateEvent.h
@@ -9,7 +9,6 @@
 #include <LibWeb/Bindings/NavigateEventPrototype.h>
 #include <LibWeb/DOM/Event.h>
 #include <LibWeb/HTML/NavigationType.h>
-#include <LibWeb/HTML/StructuredSerialize.h>
 
 namespace Web::HTML {
 
@@ -25,6 +24,7 @@ struct NavigateEventInit : public DOM::EventInit {
     Optional<String> download_request = {};
     Optional<JS::Value> info;
     bool has_ua_visual_transition = false;
+    GC::Ptr<DOM::Element> source_element = nullptr;
 };
 
 // https://html.spec.whatwg.org/multipage/nav-history-apis.html#navigationintercepthandler
@@ -54,8 +54,8 @@ public:
 
     [[nodiscard]] static GC::Ref<NavigateEvent> construct_impl(JS::Realm&, FlyString const& event_name, NavigateEventInit const&);
 
-    // The navigationType, destination, canIntercept, userInitiated, hashChange, signal, formData,
-    // downloadRequest, info, and hasUAVisualTransition attributes must return the values they are initialized to.
+    // The navigationType, destination, canIntercept, userInitiated, hashChange, signal, formData, downloadRequest,
+    // info, hasUAVisualTransition, and sourceElement attributes must return the values they are initialized to.
     Bindings::NavigationType navigation_type() const { return m_navigation_type; }
     GC::Ref<NavigationDestination> destination() const { return m_destination; }
     bool can_intercept() const { return m_can_intercept; }
@@ -66,6 +66,7 @@ public:
     Optional<String> download_request() const { return m_download_request; }
     JS::Value info() const { return m_info; }
     bool has_ua_visual_transition() const { return m_has_ua_visual_transition; }
+    GC::Ptr<DOM::Element> source_element() const { return m_source_element; }
 
     WebIDL::ExceptionOr<void> intercept(NavigationInterceptOptions const&);
     WebIDL::ExceptionOr<void> scroll();
@@ -141,6 +142,9 @@ private:
 
     // https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-navigateevent-hasuavisualtransition
     bool m_has_ua_visual_transition { false };
+
+    // https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-navigateevent-sourceelement
+    GC::Ptr<DOM::Element> m_source_element { nullptr };
 };
 
 }
diff --git a/Libraries/LibWeb/HTML/NavigateEvent.idl b/Libraries/LibWeb/HTML/NavigateEvent.idl
index 600d18fbe81..b1f96425fd3 100644
--- a/Libraries/LibWeb/HTML/NavigateEvent.idl
+++ b/Libraries/LibWeb/HTML/NavigateEvent.idl
@@ -19,6 +19,7 @@ interface NavigateEvent : Event {
     readonly attribute DOMString? downloadRequest;
     readonly attribute any info;
     readonly attribute boolean hasUAVisualTransition;
+    readonly attribute Element? sourceElement;
 
     undefined intercept(optional NavigationInterceptOptions options = {});
     undefined scroll();
@@ -35,6 +36,7 @@ dictionary NavigateEventInit : EventInit {
     DOMString? downloadRequest = null;
     any info;
     boolean hasUAVisualTransition = false;
+    Element? sourceElement = null;
 };
 
 dictionary NavigationInterceptOptions {
diff --git a/Libraries/LibWeb/HTML/Navigation.cpp b/Libraries/LibWeb/HTML/Navigation.cpp
index 0d171f121d8..a391f1c6967 100644
--- a/Libraries/LibWeb/HTML/Navigation.cpp
+++ b/Libraries/LibWeb/HTML/Navigation.cpp
@@ -911,6 +911,7 @@ bool Navigation::inner_navigate_event_firing_algorithm(
     Bindings::NavigationType navigation_type,
     GC::Ref<NavigationDestination> destination,
     UserNavigationInvolvement user_involvement,
+    GC::Ptr<DOM::Element> source_element,
     Optional<Vector<XHR::FormDataEntry>&> form_data_entry_list,
     Optional<String> download_request_filename,
     Optional<SerializationRecord> classic_history_api_state)
@@ -1011,6 +1012,9 @@ bool Navigation::inner_navigate_event_firing_algorithm(
     //     of the document's latest entry, was done by the user agent. Otherwise, initialize it to false.
     event_init.has_ua_visual_transition = false;
 
+    // 18. Initialize event's sourceElement to sourceElement.
+    event_init.source_element = source_element;
+
     // 18. Set event's abort controller to a new AbortController created in navigation's relevant realm.
     // AD-HOC: Set on the NavigateEvent later after construction
     auto abort_controller = MUST(DOM::AbortController::construct_impl(realm));
@@ -1291,9 +1295,10 @@ bool Navigation::fire_a_traverse_navigate_event(GC::Ref<SessionHistoryEntry> des
     //    navigation's relevant global object's associated Document; otherwise false.
     destination->set_is_same_document(destination_she->document() == &as<Window>(relevant_global_object(*this)).associated_document());
 
-    // 9. Return the result of performing the inner navigate event firing algorithm given navigation, "traverse", event, destination, userInvolvement, null, and null.
+    // 9. Return the result of performing the inner navigate event firing algorithm given navigation, "traverse",
+    //    event, destination, userInvolvement, sourceElement, null, and null.
     // AD-HOC: We don't pass the event, but we do pass the classic_history_api state at the end to be set later
-    return inner_navigate_event_firing_algorithm(Bindings::NavigationType::Traverse, destination, user_involvement, {}, {}, {});
+    return inner_navigate_event_firing_algorithm(Bindings::NavigationType::Traverse, destination, user_involvement, {}, {}, {}, {});
 }
 
 // https://html.spec.whatwg.org/multipage/nav-history-apis.html#fire-a-push/replace/reload-navigate-event
@@ -1302,6 +1307,7 @@ bool Navigation::fire_a_push_replace_reload_navigate_event(
     URL::URL destination_url,
     bool is_same_document,
     UserNavigationInvolvement user_involvement,
+    GC::Ptr<DOM::Element> source_element,
     Optional<Vector<XHR::FormDataEntry>&> form_data_entry_list,
     Optional<SerializationRecord> navigation_api_state,
     Optional<SerializationRecord> classic_history_api_state)
@@ -1333,13 +1339,13 @@ bool Navigation::fire_a_push_replace_reload_navigate_event(
     destination->set_is_same_document(is_same_document);
 
     // 8. Return the result of performing the inner navigate event firing algorithm given navigation,
-    //    navigationType, event, destination, userInvolvement, formDataEntryList, and null.
+    //    navigationType, event, destination, userInvolvement, sourceElement, formDataEntryList, and null.
     // AD-HOC: We don't pass the event, but we do pass the classic_history_api state at the end to be set later
-    return inner_navigate_event_firing_algorithm(navigation_type, destination, user_involvement, move(form_data_entry_list), {}, move(classic_history_api_state));
+    return inner_navigate_event_firing_algorithm(navigation_type, destination, user_involvement, source_element, move(form_data_entry_list), {}, move(classic_history_api_state));
 }
 
 // https://html.spec.whatwg.org/multipage/nav-history-apis.html#fire-a-download-request-navigate-event
-bool Navigation::fire_a_download_request_navigate_event(URL::URL destination_url, UserNavigationInvolvement user_involvement, String filename)
+bool Navigation::fire_a_download_request_navigate_event(URL::URL destination_url, UserNavigationInvolvement user_involvement, GC::Ptr<DOM::Element> source_element, String filename)
 {
     auto& realm = relevant_realm(*this);
     auto& vm = this->vm();
@@ -1364,9 +1370,9 @@ bool Navigation::fire_a_download_request_navigate_event(URL::URL destination_url
     destination->set_is_same_document(false);
 
     // 8. Return the result of performing the inner navigate event firing algorithm given navigation,
-    //   "push", event, destination, userInvolvement, null, and filename.
+    //   "push", event, destination, userInvolvement, sourceElement, null, and filename.
     // AD-HOC: We don't pass the event, but we do pass the classic_history_api state at the end to be set later
-    return inner_navigate_event_firing_algorithm(Bindings::NavigationType::Push, destination, user_involvement, {}, move(filename), {});
+    return inner_navigate_event_firing_algorithm(Bindings::NavigationType::Push, destination, user_involvement, source_element, {}, move(filename), {});
 }
 
 // https://html.spec.whatwg.org/multipage/nav-history-apis.html#initialize-the-navigation-api-entries-for-a-new-document
diff --git a/Libraries/LibWeb/HTML/Navigation.h b/Libraries/LibWeb/HTML/Navigation.h
index 342b962b7c8..767679714ac 100644
--- a/Libraries/LibWeb/HTML/Navigation.h
+++ b/Libraries/LibWeb/HTML/Navigation.h
@@ -116,10 +116,11 @@ public:
         URL::URL destination_url,
         bool is_same_document,
         UserNavigationInvolvement = UserNavigationInvolvement::None,
+        GC::Ptr<DOM::Element> source_element = {},
         Optional<Vector<XHR::FormDataEntry>&> form_data_entry_list = {},
         Optional<SerializationRecord> navigation_api_state = {},
         Optional<SerializationRecord> classic_history_api_state = {});
-    bool fire_a_download_request_navigate_event(URL::URL destination_url, UserNavigationInvolvement user_involvement, String filename);
+    bool fire_a_download_request_navigate_event(URL::URL destination_url, UserNavigationInvolvement user_involvement, GC::Ptr<DOM::Element> source_element, String filename);
 
     void initialize_the_navigation_api_entries_for_a_new_document(Vector<GC::Ref<SessionHistoryEntry>> const& new_shes, GC::Ref<SessionHistoryEntry> initial_she);
     void update_the_navigation_api_entries_for_a_same_document_navigation(GC::Ref<SessionHistoryEntry> destination_she, Bindings::NavigationType);
@@ -154,6 +155,7 @@ private:
         Bindings::NavigationType,
         GC::Ref<NavigationDestination>,
         UserNavigationInvolvement,
+        GC::Ptr<DOM::Element> source_element,
         Optional<Vector<XHR::FormDataEntry>&> form_data_entry_list,
         Optional<String> download_request_filename,
         Optional<SerializationRecord> classic_history_api_state);
diff --git a/Tests/LibWeb/Text/input/wpt-import/navigation-api/navigate-event/event-constructor.html b/Tests/LibWeb/Text/input/wpt-import/navigation-api/navigate-event/event-constructor.html
index a7d86b9a75f..d83c3cdf283 100644
--- a/Tests/LibWeb/Text/input/wpt-import/navigation-api/navigate-event/event-constructor.html
+++ b/Tests/LibWeb/Text/input/wpt-import/navigation-api/navigate-event/event-constructor.html
@@ -78,8 +78,7 @@ async_test(t => {
     assert_equals(event.downloadRequest, downloadRequest);
     assert_equals(event.info, info);
     assert_equals(event.hasUAVisualTransition, hasUAVisualTransition);
-    // NavigateEvent sourceElement is still in development, so test whether it is available.
-    if ("sourceElement" in e) assert_equals(event.sourceElement, sourceElement);
+    assert_equals(event.sourceElement, sourceElement);
   });
   history.pushState(2, null, "#2");
 }, "all properties are reflected back");
@@ -99,8 +98,7 @@ async_test(t => {
     assert_equals(event.formData, null);
     assert_equals(event.downloadRequest, null);
     assert_equals(event.info, undefined);
-    // NavigateEvent sourceElement is still in development, so test whether it is available.
-    if ("sourceElement" in e) assert_equals(event.sourceElement, null);
+    assert_equals(event.sourceElement, null);
   });
   history.pushState(3, null, "#3");
 }, "defaults are as expected");