It seems problematic to allow arbitary non-lowercase attribute on HTML nodes. Because the server has no ability to keep them case sensitive (HTML isn't). So they will end up different on the client.

We should probably warn if the attribute is not a known one *and* is not lowercase.
});
        it('should not blow away user-entered text on successful reconnect to an uncontrolled checkbox', () =>
          testUserInteractionBeforeClientRender(
            <input type="checkbox" defaultChecked={true} />,
            true,
            false,
            'checked',
          ));
        it('should not blow away user-entered text on successful reconnect to a controlled checkbox', async () => {
          let changeCount = 0;
          await testUserInteractionBeforeClientRender(
            <ControlledCheckbox onChange={() => changeCount++} />,
            true,
            false,
            'checked',
          );
          expect(changeCount).toBe(0);
        });
        
        
        xit(
          'should not blow away user-entered text on successful reconnect to an uncontrolled textarea',
          () =>
            testUserInteractionBeforeClientRender(
              <textarea defaultValue="Hello" />,
            ),
        );
        
        
        xit(