I saw this asked in a Facebook group and I have recently been asked to provide a step by step on how to add the functionality to a divi full width header module
This was only intended to be a quick fix solution and will only work if you have a free button from the two available in the full width header module. If both buttons are in use you will need to find another solution.
Remember to include the url in the button url section. the button text is not important as it wont show, so enter anything in there.
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