TYPO3 Core

I set up a double mount point.

My pagetree looks like this :

PAGE 1 [ MP -> 2]
  PAGE 2
 |_ PAGE 3 [ MP -> 4]
  PAGE 4 
 |_ PAGE 5

On page 3 (wich is a mounted point), the option "Substitute Mount Point (this page) with Mounted page" is checked.

Inside page 4, I inserted a link which points to page 5.

But the link is not working inside the double mounted points.

link is index.php?id=5&MP=2-1 instead of index.php?id=5&MP=2-1,4-3

One mount point is missing.

To solve the problem, I unchecked the option "Substitute the mount point" in page 3.
And get the content from page 4 using typoscript.
(issue imported from #M3972)