Yes it is true. I made some experiments with that functions 'connection_abortes()'. First a source made an error, which I see. They wrote: ignore_user_abort();
But that only gives you the status of the 'Abort-Setting'.
So I try (with little hope)
'ignore_user_abort(true);'
And as I readout the setting it has changed it...
Next I see that the script runs after I disconnect with the site. But other experiments fail. I try some things and then it
was logical after an experiment: flush() is one of the necessary things. Without those output to the client the function
'connection_aborted()' stays on 'false'
The Second is that you have to output something. Without that it also doesn't works.
So I now know that you have to echo something and then output the buffer. Only then 'the Script' (or the function)
'knows' that the client is disconnected.