Vue app does not work in an older browser

Problem description

You might ask, what can I do. Wasn’t the app supposed to work just fine in legacy browsers if scaffolded with Vue-CLI? Yes, it was supposed to. You open your app in Internet Explorer, and you are welcomed by a white screen and errors in the console. This can be very problematic to solve, especially in browsers like IE that have really terrible error messages. It’s like trying to find a needle in a haystack.