I see there has been a lot of discussion about Preview not working. I am having that problem with 8.9.1 (running on an M1 Mac) when I add a new page. All my old pages created on earlier versions of RW are fine.
I went back to 8.9 and then 8.8 and 8.0 but still have the same problem. The earlier posts I read say they saw a blank screen; what I see is a page of code.
Anyone have any suggestions about this? Jannis from InStacks (who I contacted because I thought it was a problem with the stacks I was using) advised me: “something with the PHP execution of the preview server does not work. RW should take care of this automatically. If reinstalling RW doesn’t help, mention this to the support team.”