CheckboxEditor and BooleanFormatter: bug?

I have some code that shows a DataTable, and one of the fields is meant to be an editable checkbox. The code below should work; unfortunately it only shows a blank cell and no editing is possible. Looking at the HTML produced, the div itself is empty when not selected, and filled with a zero height input checkbox when selected.

Am I doing something wrong or is this a bug?

columns_controls=[TableColumn(field=‘Test ID’, title=‘Test ID’,width=60),
TableColumn(field=‘Field’, title=‘Field’,editor=StringEditor()),

TableColumn(field=‘Length’, title=‘Length’,editor=CheckboxEditor(), formatter=BooleanFormatter(icon=‘check’)),

]

tab_controls=DataTable(height=“auto”, source=source_controls

,columns=columns_controls,fit_columns=True,editable=True)