How does a website (or podcast) send out notification of updates?
I have subscribed to a sample podcast and see that I do get alerts (upper right corner of screen) on my MacBook. I have not yet verified those alerts only show up when I have Chrome opened, but that because I always have Chrome open.
Here is what I see under Settings as the Allowed sites.
What is port 443?
Does this mean my port 443 is open to alerts from these two websites?
Please let me know how this works, since I am considering using this for my podcast. Or, if you give me the name of this type of communications, I can look for solutions which I can adopt to have this behavior.