Hello, InFaassie
We are thinking that this issue is related more to WordPress functionality in combination with your version of the operating system. We didn’t have any such questions from our customers yet. Checking a few articles on Google and found that such errors happens with some specific Operation systems -> https://github.com/GLVis/glvis/discussions/141 (macOS Catalina 10.15.7) and https://stackoverflow.com/questions/30669659/multiproccesing-and-error-the-process-has-forked-and-you-cannot-use-this-corefou.
Could you contact WordPress support about this question and at the same time also ask your hosting provider about this issue (maybe your hosting had heard about this during his life experience)? If you find any solutions, please, give us feedback so that we will grow together in technologies and know the answer to how it could be fixed.
Kind Regards,
8theme team