If memory serves, you have to do it from the Media page, Media Storage panel, and use the Add Folder... option with (Create Bins). Then you can right click the bin and use one of the Resync options.
Although...looking in the 20 Beta, I see those Resync options for bins that were
not created that way, sooooo...maybe I'm wrong? Or maybe things changed in version 20?
Not sure.
