Formula to test if formula Rich Text lookup field is blank?

I have a formula rich text lookup field on a child record. The actual field is a rich text formula field that shows a url and a custom name for the url.

On the child record, I simply want a formula to see if it is blank. However, [RIch Text Lookup FIeld]="" does not work. I am thinking that the formula itself is preventing it from being seen as blank?

I have a very easy workaround if needed. I can bring another field down to the child and use that, so this isn't holding me up from accomplishing what I need to.

But I thought it was interesting and was wondering if there is a way to tell if a rich text formula lookup field is blank.

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Mike Tamoush
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