Response not JSON!

Im getting this error ('Response not JSON') every time I open a template in admin and every time I save a file. If I ignore the popup all is running as expected. However I would like to know what it means so I can fix it.
On the forum Ive noticed sometimes (not all the time intermittently ) it loads a blank page and if I refresh it loads as expected not a major issue but annoying, Im wondering if these things are related.

I don't think this is a bug its something Ive done as Ive made lots of changes ;)

Just would like to know what it means.

Jake Bunce

XenForo moderator
Staff member
Any errors in the log?

Admin CP -> Tools -> Server Error Log

Also try disabling any addons to see if that affects the error.

Also a blank page is often a suppressed error. Try adding this line to your library/config.php file to see if that reveals any specific error message on the blank page:

ini_set('display_errors', true);
Just done that there are no errors, I have errors set in my php.ini file so I don't think that made any difference.
It feels like a java script thing to me but I can't locate it at the moment. Just wondering what the message meant as it might help my investigation into the problem.