We have some pages with a "|" in its title.
If you try to display all children of this page, the children-macro will fail.
It seems the "|" is not escaped properly.

If we create a page without that pipe ("|"), create a few children pages, insert the children macro on a different page to the first page and after that, we rename the site with a pipe ("|") in it, the children macro works fine. But now we are editing something else on this page and safe, then the macro is broken again.