Can you clarify what you mean. If you replace all the spaces with a letter and format that letter as white coloured, then you get one very long word per paragaph which will probably play havoc with your formatting and end the ability to spell check the document. It can nevertheless be done using the replace function (CTRL+H) replace space with the letter and format the replacment font as white coloured.

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Graham Mayor - MS MVP (Word) (2002-2019)
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