I cannot see an issue here.
Was retested with the latest version with a new project with a few controls dropped on it and the code
procedure TForm2.WebButton1Click(Sender: TObject);
var
i: integer;
begin
for i := 0 to ComponentCount - 1 do
begin
weblistbox1.Items.Add( self.Components.Name);
end;
end;
and this shows all found components in the listbox
