Jonathan Moore

>error_log the url of every http request, to find out in which requests the issue
Well Apache should already do that, not sure what logging from the app would most help

>The Abandoned Cart plugin is not in the status
Yes I turned it off in case it was the problem

>Did emptying the wrappers array help at all?
I didn’t do that yet, I will

>If instead of disabling our plugin completely, just disabling AutoCoupon
Well this is the functionality mainly used so not so keen on disabling it

Thanks, some more things to try