Scratch that.
This means there is something in my files which deviates from the norm.
This is why I don't ever like touching anything in the core as it tends to have a knock on effect elsewhere
It's still switched on for now until I can find out what's wrong with the core code which it doesn't like.
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Update: It's showing the conflict is in a mobiquo file which is tapatalk.
I may have to uninstall tapatalk before I can dig deeper, so its not a 5 min job I can do now.