Cannot delete custom capability

Hi,

I have created a custom capability with Roles & Capabilities for testing purposes. Now, it’s no longer used by any role and I wanted to delete it. I opened the capabilities page, checked that custom capability, selected Delete in the bulk actions list and clicked on Apply. I immediately got an error message :

Please select at least one item to perform this action.
Veuillez sélectionner au moins un élément pour effectuer cette action (in french)

Is this a known issue ?

Thanks in advance.