More and more people are living and working through their browser. You check your mail, your social media, perhaps a travel site all living in the cloud. The key is that you need an account with each of these, and managing these accounts can be a pain. Then along comes BRM and you suddenly need more accounts!
Profiles to the rescue.
If you have more than one shop with BRM, or if you have more than one user on the same computer, you're going to want to use multiple profiles in your browser. You can do this easily with Firefox and Chrome.
Personally, I find this extremely useful as I have one account for my own bike shop, and another account to problem solve with any users' systems. It's very simple to set up and you can even change the 'template' for each profile so they look very different. (as well as having different icons). For example, the shop Village Velo has red colours, so I make that browser bright red.
How to do it?
in Chrome you simply do the following:
here is the official Google explanation:
here is the firefox documentation here
Here is another useful article on the subject.