I have being using Chrome Profile(People) feature since they were introduce. It has been a god send for me. I tried Firefox containers for a couple of days here a couple things that will really help:

* Containers need to be per window. Keeping track of containers at Tab level is lot of mental work.

* Set a different default container per device. For example I want to set different default for an office laptop, home computer, shared device, etc.

Firefox is getting there i feel it is just moving too slow for me to make a complete switch.