Thank you for looking into this. Yes, I too am just relieved the code is functioning despite the error/warning, whch I did too reckon it shouldn’t have worked for everyone else. I also hope the fact that the site was migrated from a WHM/CPanel account and onto this (Cloudways control using DigitalOcean droplet) doesn’t have anything to do with it.
I have done what you instructed and changed the line (and commenting-out the previous line). Additionally, I purged Varnish from the server and restarted it. Unfortunately, the symptom persists.
I have indeed tried to engage Cloudways into this and they have tried (in their limited capacity in the context of the plugins) to look into it, but to no avail.
I hope that helps? (Please let me know if you prefer to have server admin access, and I’ll be happy to set such an account for you.)
All the best,