What I did was: Finder> File> "Add to sidebar"
I see no option to "delete from sidebar"
I even went into "Finder preferences"> Sidebar, and the folder that now exists is not on the list of things to show under "places" where the document is currently showing up on sidebar.
H E L P (Damsel in distress)
Select the item, drag it out of the Sidebar until it poofs away. You may need to hold down the OPTION or COMMAND key while you do that in case it does not work as described.
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