It's ridiculous that I have to write it, but it looks like there is no hope in this being an actual feature of the Microsoft Edge web browser - setting a blank new tab. Not a tab with minimal ads, but just one that is blank. You know, the thing that you could set in Firefox for ages.
Recently I’ve been reading a tech site on my iOS device when a new tab opened and went into the background - something I’ve seen before caused by rogue ads that are fetched via normal means (e.g. embedded in a legit page), so my next steps were not unusual - go to the tab and close it. Here is what I faced: Once the tab opened, I instantly recognized it as one of those tech support scams.