[Question]: Can the editor be instructed to ignore a class?

You could place a listener on a new selector

editor.on('selector:add', selector => {
		const name = selector.get('name');

      	if (someConditionForSelectors(name)) {
			selector.set({
				// Can't be seen by the style manager, therefore even by the user
				private: true,
			})
      	}
});

What do you mean "to ignore"? To ignore where? Being available in the style manager or something else?

Sorry, I was unclear there. When clicking an element/block and proceeding to styling the element, the class is chosen by default. Could this class be deselected by default and hidden from the Classes field?