How to disable Bulk Deletion of custom fields

[Nicolas Bourdages _Ubisoft_]

Ever since 8.16 on Jira Data Center, admins can delete custom fields in bulk. However, we don't want that feature, it's quite dangerous and there's very few legitimate use cases for us. Has anybody found how to disable that function? I'm searching through the system modules and can't find anything, and would rather disable it with native functions rather than do some javascript to hide the UI elements.

Thanks,

Nicolas