I’m having the same issue with two of my pages. I can view the pages fine but keep getting the error:
The site is experiencing technical difficulties.
when I either click the Edit button on the WordPress toolbar or when I try to open the page in WordPress’ admin area.
The pages in question have complex page templates and layouts with lots of repeaters and content added to them (it can sometimes take a minute or two for changes to save).
I’m using Advanced Custom Fields PRO Version 5.8.4 and WordPress version 5.2.3
