3 files changed, 17 insertions, 8 deletions
diff --git a/Userland/Libraries/LibWeb/DOM/Element.idl b/Userland/Libraries/LibWeb/DOM/Element.idl
index e2d461d8bb..0baea125da 100644
--- a/Userland/Libraries/LibWeb/DOM/Element.idl
+++ b/Userland/Libraries/LibWeb/DOM/Element.idl
@@ -1,6 +1,7 @@
 #import <CSS/CSSStyleDeclaration.idl>
 #import <DOM/ChildNode.idl>
 #import <DOM/DOMTokenList.idl>
+#import <DOM/InnerHTML.idl>
 #import <DOM/NamedNodeMap.idl>
 #import <DOM/Node.idl>
 #import <DOM/NodeList.idl>
@@ -29,9 +30,6 @@ interface Element : Node {
     HTMLCollection getElementsByTagNameNS(DOMString? namespace, DOMString localName);
     HTMLCollection getElementsByClassName(DOMString className);
 
-    // FIXME: This should come from a InnerHTML mixin.
-    [LegacyNullToEmptyString, CEReactions] attribute DOMString innerHTML;
-
     [Reflect] attribute DOMString id;
     [Reflect=class] attribute DOMString className;
     [SameObject, PutForwards=value] readonly attribute DOMTokenList classList;
diff --git a/Userland/Libraries/LibWeb/DOM/InnerHTML.idl b/Userland/Libraries/LibWeb/DOM/InnerHTML.idl
new file mode 100644
index 0000000000..5fce4cd4f5
--- /dev/null
+++ b/Userland/Libraries/LibWeb/DOM/InnerHTML.idl
@@ -0,0 +1,7 @@
+// https://w3c.github.io/DOM-Parsing/#the-innerhtml-mixin
+interface mixin InnerHTML {
+    [LegacyNullToEmptyString, CEReactions] attribute DOMString innerHTML;
+};
+
+Element includes InnerHTML;
+ShadowRoot includes InnerHTML;
diff --git a/Userland/Libraries/LibWeb/DOM/ShadowRoot.idl b/Userland/Libraries/LibWeb/DOM/ShadowRoot.idl
index 769bf4b3ac..d1efd129d0 100644
--- a/Userland/Libraries/LibWeb/DOM/ShadowRoot.idl
+++ b/Userland/Libraries/LibWeb/DOM/ShadowRoot.idl
@@ -1,11 +1,15 @@
 #import <DOM/DocumentFragment.idl>
+#import <DOM/InnerHTML.idl>
 
+// https://dom.spec.whatwg.org/#shadowroot
 interface ShadowRoot : DocumentFragment {
-
+    // FIXME: mode should return a ShadowRootMode
     readonly attribute DOMString mode;
+    // FIXME: readonly attribute boolean delegatesFocus;
+    // FIXME: readonly attribute SlotAssignmentMode slotAssignment;
     readonly attribute Element host;
-
-    // FIXME: This should come from a InnerHTML mixin.
-    [LegacyNullToEmptyString] attribute DOMString innerHTML;
-
+    // FIXME: attribute EventHandler onslotchange;
 };
+
+enum ShadowRootMode { "open", "closed" };
+enum SlotAssignmentMode { "manual", "named" };