Having upgraded one of my Digital Ocean droplets to the latest Ubuntu 16 and updating to PHP v7.2 I noticed a number of ajax errors. The web inspector showed the error as “Cannot decode raw data (NSURLErrorDomain:-1015)”. When investigating the problem further I simply echo’d out some “hello worlds” in the controllers directly which worked fine as long as I didn’t echo a variable. When doing this I had to include exit; at the end of the method. This fixed the problem but wasn’t clearly a sustainable fix. The problem I later traced to the config file which had “$config[‘compress_output’] = ENABLED;” set to enabled. I changed this to FALSE and then everything work fine. Odd. Hopefully this helps someone else.