Disable Links in Rich Text

Hi

I'm trying to disable Links in a Rich Text control - following these instructions:

http://dev.day.com/docs/en/cq/current/administering/configuring_rich_t ext_editor.html#Overriding Default Features

I have created a node rtePlugins/links with a property features (String[]) set to no value

The Links still display in the dialog

I have also created a node rtePlugins/tables with a property features (String) set to "*"

Tables are enabled

I am using AEM5.6 - should I be able to disable links?

Thanks

Tim