submenu arrow

packages/editor/src/components/menu/Menu.vue

@@ -19,6 +19,7 @@
             :id="item.id"
             :items="item.children"
             trigger="hover"
+            submenu
             :position="position"
             :disabled="item.disabled"
             >{{ item.label }}</Menu
@@ -65,6 +66,7 @@ const props = withDefaults(
     openSibling?: string;
     open?: boolean;
     disabled?: boolean;
+    submenu?: boolean;
   }>(),
   {
     position: 'bottom',
@@ -89,6 +91,7 @@ const menuClass = computed(() => [
   'menu-wrapper',
   isOpen.value ? 'menu-wrapper--open' : 'menu-wrapper--closed',
   `menu-wrapper--${props.position}`,
+  props.submenu ? 'menu-wrapper--submenu' : '',
 ]);
 
 const menuStyle = computed(() =>
@@ -162,6 +165,18 @@ watch(
       right: 100%;
     }
 
+    &.menu-wrapper--submenu > .menu-button::after {
+      content: '';
+      position: absolute;
+      width: 0;
+      height: 0;
+      border-top: 0.375rem solid transparent;
+      border-bottom: 0.375rem solid transparent;
+      border-left: 0.375rem solid rgb(87, 87, 87);
+      right: 0.25rem;
+      top: 0.6875rem;
+    }
+
     &--open > .menu-button {
       background-color: #e6e6e6;
     }

packages/editor/src/components/sidebar/SidebarRow.vue

@@ -137,7 +137,9 @@ const menuItems = computed(() => [
   {
     id: 'add',
     label: 'Add...',
-    disabled: (props.item as GameObject).virtual,
+    disabled:
+      (props.item as GameObject).virtual &&
+      (props.item as GameObject).objectType !== 'World',
     children: Object.keys(instancableGameObjects).map((item) => ({
       id: item,
       label: item,