Previously the common tip to apply a leader without the text in Revit was to create a blank annotation family that does not have anything inside, but now you don’t need to create an extra family for this.
I am not sure when Autodesk updates this feature, but Revit 2019 allows us to place a leader without the text. You can simply place a leader and do not add a text, or add a leader to the existing text and remove the text note.
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