Originally posted by Complaintdesk:

All crafting workbenches & fire sources (don't have to be lit) prevent mob spawning. That's pretty much the list other than a few peripherals such as beds, portal and manufacturing items. My friend has done all the research check out his video https://www.youtube.com/watch?v=_C9fKFg6bmw

This is exactly video I mentioned before, just didn't linked. Thanks.