TPix-John

Just to clarify…
I have tried to add a slide in both Chrome and Firefox Developer Edition latest builds and the same issue occurs.

Any update on this?
The issue is persisting still on WP 4.8.1 and FRS 2.3.1

I had the same issue with WordFence not being able to create the wfcache folder. So I created it manually via FTP with (initially) 755 as the permissions set.
However, WF indicated that it could still not write in this folder so I changed to 777.

Not sure where to go from here… it’s working but I’m not wholly comfortable with a folder sitting there with that level of permissions.