People need to be more patient. It's only been just over 36 months since this request was first made. It's not like there are any other browsers with this type of feature available that one can look at for inspiration. Let alone source code to browse. At least if there was already some type of mockup, it might make it easier to figure out how to implement.
But things take time and I'm sure when MacOS 20 is released, everyone will be able to use containers, or sessions, or buckets, or grease pots, or cubbies, or dank-pockets or whatever you'd like to call the fature. We all know what it means.
