I have to use five different browsers (and occasionally a couple more) to do the web surfing I do. Oh, I don’t _have_ to, but different sites just work differently in different browsers, even if they use the same rendering engine. And some browsers just have features that work well for certain things. Example: If I want to do some searches on topics that are just none of anyone’s business to track (say, procedures and methods for NONE OF YOUR BUSINESS *heh*), I use a TOR-enabled browser in addition to a good VPN, etc. But if I’m just comparing some items at a shopping site I use regularly, I don’t use that one because my fav TOR-enabled browser has lousy tab stacking, so I use one that can auto-stack tabs from the same host. Just different capabilities. If there are a lot of videos on my download list for the day, I use an entirely different browser that is the one I have found to be able to do that task most easily.
And sometimes I use one that offers really nice video backgrounds on its speed dial page, just ‘cos they’re “purtier” than what’s offered on any of the other browsers I use. So?