This box is always gray. How to make it active box?
Try and Uncheck -Create dimension only when value is entered.
I never noticed that option before, but now that I have I can't figure it out either. I keep the option shown below turned on, so I don't really need it anyway.
Like Glenn Schroeder showed make sure the "create dimension only when value is entered" box is un checked.
Then you can check the add dimension box.
Don't use this personally, but I figured I could answer the question.
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