When closing an unpublished draft page with the browser back button, that page will not be shown in the page tree

Issue Summary

When closing an unpublished draft page with the browser back button, that page will not be shown in the page tree

Steps to Reproduce

1. Click the [+] button on the left of the title of the parent page in the page tree
2. Add page title and page body
3. Close an unpublished draft page with the browser back button

Expected Results

The draft page appears undet the parent page in the page tree like below:

▽ Parent page
    * Untitled [Draft] 

Actual Results

We can expand the tree, but the draft page does not appear under the parent page in the page tree like below:

▽ Parent page

Based on the DB, the draft itself is created successfully.

Workaround

Copy the parent page and use the copy page (and delete the original one if needed)