This is actually surprisingly complicated as there are 256x256x256 possible colours and lots of places that colour could be applied (inline text, text boxes, comments, footnotes, headers, footers, smart art, tables, paragraph shading etc)

The first macro would be simpler but it would likely remove any 'differences' that would be required for the second macro to restore the original colours.

If your documents were well structured and either used theme palette colours OR character styles to set the colours then you might get the desired result but that is kind of unlikely.

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Andrew Lockton
Chrysalis Design, Melbourne Australia