Disable window list header and select the first one in the list below

__tests__/src/components/WindowList.test.js

@@ -84,4 +84,30 @@ describe('WindowList', () => {
       ).toBe(true);
     });
   });
+
+  describe('with multiple windows', () => {
+    beforeEach(() => {
+      windows = {
+        zyx: { id: 'zyx', manifestId: '123' },
+        xyz: { id: 'xyz', manifestId: 'abc' },
+      };
+      manifests = { abc: { manifestation: { getLabel: jest.fn(() => [{ value: 'Some title' }]) } } };
+
+      wrapper = shallow(
+        <WindowList
+          containerId="mirador"
+          anchorEl={{}}
+          manifests={manifests}
+          windows={windows}
+          handleClose={handleClose}
+          focusWindow={focusWindow}
+        />,
+      );
+    });
+
+    it('has the first window in the list selected', () => {
+      expect(wrapper.find('WithStyles(MenuItem)').first().props().selected).toBe(true);
+      expect(wrapper.find('WithStyles(MenuItem)').last().props().selected).toBe(false);
+    });
+  });
 });

src/components/WindowList.js

@@ -39,13 +39,14 @@ export class WindowList extends Component {
         open={Boolean(anchorEl)}
         onClose={handleClose}
       >
-        <ListSubheader>
+        <ListSubheader role="presentation" selected={false} disabled tabIndex="-1">
           {t('openWindows')}
         </ListSubheader>
         {
-          Object.values(windows).map(window => (
+          Object.values(windows).map((window, i) => (
             <MenuItem
               key={window.id}
+              selected={i === 0}
               onClick={(e) => { focusWindow(window.id); handleClose(e); }}
             >
               {