How to solve the "Cannot load a form that has itself as ancestor" error in Delphi

How to solve the "Cannot load a form that has itself as ancestor" error in Delphi

This is how a new/empty project should look like:

uses
  Forms,
  Unit1 in 'Unit1.pas' {Form1};

And this how your project probably looks like:

uses
  Forms,
  Unit1 in 'Unit1.pas' {Form};    <--------- here="" missing="" span="">

I spent on hour to find the well hidden culprit.
I had a previous problems where Delphi messed up the DPR file (the {$R *.res} declaration).
When do we ever learn?