So I have a huge library ok. And we have different software releases, some of them at the same time. Each release is also a library for the new releases. And today I realized that the rendering does not work properly. Sometimes the screens does not appear at all and show up only blank, in other cases parts of the screens like text in tables and stuff or complete elements are missing. So if you open up the instance on the left layer area than everything looks fine again (for that one screen).
Like in this case here (Stuff is pixelated for safety reasons. The customer would see me in Jail if I post it here unpixelated). I open up the page with the screens I want to take a look at and the left screen is broken:

If I doubleclick on the left screen the layout comes back like:

And now you guys, what could that problem be?
Love and Peace,
Jean-Marc