OK. I’ve worked it out. I apologise and I’m very grateful for all of the time that you’ve given into looking at this for me. But it seems that if I had taken a look into the actual script I would have found the problem immediately. I was just editing it to add some debugging and the first thing I see is this on line 10 of index.php:
error_reporting(E_ERROR | E_PARSE);
Guess what? If I change that to E_ALL then it outputs the error!
2018/01/22 14:31:05 [error] 17546#0: *7762 FastCGI sent in stderr: "PHP message: PHP Warning: require_once(…/…/config.php): failed to open stream: No such file or directory in /usr/home/matt/www/ttrss/plugins.local/repos/fever/fever/index.php on line 12
So the actual root cause is how I install plugins.
in ttrss/plugins.local I have a repos directory. Inside that I git clone the fever repo. I then symlink ttrss/plugins.local/fever to ttrss/plugins.local/repos/fever/fever.
This means that when it’s looking for config.php it’s looking in the wrong directory as you are doing require_once “…/…/config.php”;
The previous code didn’t hardcode it like this. It used $tt_root = dirname(dirname(dirname($_SERVER[‘SCRIPT_FILENAME’])));
So at least now I know the problem and how to fix it.