@Born-in-Gva I don't know anyone who only has one browser installed on their device. Even my cell phone has like 5 different browsers on it.
Opera works great on 99.9% of websites. On the rest, I use a different browser. It doesn't mean you have to use that browser all the time, just when you log in to certain sites. You do not have to swear allegiance to those browsers. Just log in to your bank, do your business and log out and go back to your default browser.
I have this issue with my insurance company. I also have or had this problem with logging into the web UI for some of my newer surveillance cameras which is infuriating.
I also used to have another need to temporarily use Safari browser when I wanted to use ApplePay. That's no longer required but it used to be.