Sound indicators ... that time? Like a year ago?
I understand your jest, but for reference by "that time" I referred to back when pop under were still a thing.
Searching for which tab makes sound is one thing, searching for it and not finding it anywhere because it's a pop under positioned at the bottom right of your screen is a whole other experience.
Nothing quite like those search that took you on sketchy websites and their porn pop under blasting orgasmic noises in your home / office while you frantically try to find who does that (and then close everything because it's taking too long).
"The good old time", as they say.