Clicking close after attempting to edit a restricted page you do not have editing rights on results in a blank page

Summary

If you are an admin and you don't have permission to Edit a page, you still are allowed to edit it, but if you click on the close button, it loads a blank page. The page doesn't refresh or redirect you back to the view mode of the page as expected.

If you click on save, you will receive a Not permitted message.

The main problem is when you click on Close, the page returns blank.

Steps to Reproduce

1. Create a 'test' user.
2. Create a page with the 'test' user account and restrict the editing to that user.
3. With a Confluence admin account, go to the restricted page.
4. Click on Edit and then in Close.

Expected Results

You are redirected back to the page.

Actual Results

The page returns blank.

Workaround

No workaround available.