Hi,
The problem is site wide, I have 2 headers and 2 footers, assigned through language tag of polylang.
This works flawlessly once it works, but if you then touch a header or footer, by as much as changing a font setting on one of its elements, there is a chance that no footer and headers are shown. So if I edit the English footer, and the problem occurs, then also the Dutch header is not shown.
It can be solved by just fidling around with arbitrarry changes to the footer in any element.
The information for the website is above in a secure note