Cloner Plugin not working / Access-Control-Allow-Origin issues?

When I try to use the cloner plugin, the front-end stalls due to several 'Access-Control-Allow-Origin' header errors. I have tried disabling the domain mapping plugin and W3 Total Cache, but I still receive the errors on the front-end. I did check with DreamHost VPS support and no errors were occurring in the server logs.

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