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Continue to ChatQuery : Do you use a Facebook application ID? If you do, you should see a link under the comments box plug-in where you can administrate/moderate comments. I think there is an option there for you https://vmapp.org/query/73312/Do-You-Use-A-Facebook-Application-ID-If-You-Do-You-Should-See-A-Link-Under-The-Comments-Box-Plug-In-Where-You-Can-Administrate-Moderate-Comments-I-Think-There-Is-An-Option-There-For-You/