I think they may be referring to this dialog:
But that really makes no sense as it only describes whatever topic is being displayed in the editor. Oh, and to see the dialog you have to first be viewing the Tag List ( View > Show > Tag List )
Then you double-click the word Document in the Tag list.
I'm thinking for a more complete picture concerning word count, you probably should generate Printed Documentation to create a Microsoft Word document. Then use Microsoft Word's word count feature.
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