TYPO3 Core

The page property "php_tree_stop" should not expand the branch of the page tree from that page. Instead it should show a red "+" which indicates that the page tree stops here and cannot be expanded. Clicking the red "+", the page will become a temporary mount point in the navigation frame.

The page tree is not stopping the branch from displaying and the red "+" is not available, so there is no way to stop expanding the tree from that point. You can never get a temporary DB mount, since the link is not in the tree.

Other functionality, where a part of the tree is shown, like the "New Record" wizard, where you can set the position of the new page, is showing the red "+", but clicking on it will not create a temporary DB mount.