Navigation Panel shows hidden pages

We have a xwiki with a subwiki. The main wiki until now has only one created page with a redirect to this sub wiki. (We are preparing this whole wiki for many more sub wikis and the main wiki should be the starting point for all the sub wikis.)

In this main wiki we hid all pages in the navigation panel accept that one we created ourselves. This is working as long as we are everywhere in the main wiki except bin/view/Main/. Every time we request this one page (e.g. by clicking the company logo) all hidden pages (spaces) suddenly appear in the navigation panel and stay until we go to anywhere else in the main wiki.

As far as I see this does not happen inside the sub wiki. We had several instances of xwiki for testing purpose. So I can say that we saw this in 13.10.1 Debian, 13.10.6 Debian and 12.10.x/13.10.x Jetty.

Any ideas?
Regards, Simpel

Now I have to add: it’s not just only happening on /Main. And my collegue said it was in sub wiki too.

But only if (with x+x+x+h) seeing hidden pages where active. Toggling this two times with x+x+x+h it’s gone.

Does this ring a bell?

Update: Toggling doesn’t help every time.