Reloading the editor when using a duplicated page title doesn't work on Confluence 5.8

Steps to reproduce:

1. Create a space with versions and duplicate page title

2. Create a page "page"

3. Create a second page, set the title to "page" int the editor

4. Save the page

5. The page is reloading because a page with this title already exists

Expected result:
The editor is loaded normally and the permalink is appended with "+1"

Actual result:
Permalink and title are not displayed in the editor
When saving the page again, this causes an encoding error and the page isn't saved

Workaround:
Modify/cChange permalink manually before clicking Save button, this way page with same titles but different permalink will be able to save.