Broken navigation panel after using pinned pages

Reproduction steps:

• On a fresh wiki create a page named "Before A"
• The navigation panel should contain "Before A" and then "Home"
• Go to administration > Navigation Panel
• Pin "Before A"
• Save the changes and go back to main page

Expected result:

• Before A is pinned and displayed as first page of the navigation menu

Obtained result:

• Two entries are displayed first in the navigation menu: "Before" and then "A" and both leads to unexisting pages