I've never used Opera before, so I might give it a go to see how it fairs.
I had to use IE(old ass version too) for a certain application at worked because it wouldn't work on any other browser. It was awful and dumb. We now use an updated version of it, which can be used on other browsers.
Yeah the company I work for is currently using IE 11 for its transactions and all but since IE is getting discontinued , my team is currently in talks with the software developer to get it up and running for Google Chrome (which is also recommended for another application we use).
Gonna be fun exploring what settings, bugs come across when we start deploying that lol.