> An in-app notification pop-up will alert you to the change. You can opt out in the pop up.

The in-app notification that I got was a pop up which contained some buttons and some images. There was no text. Just in case it was some dark mode issue I checked the DOM and I couldn't find any text there either. I just clicked outside the modal and it went away. I assumed it was some announcement about some new feature and ignored it.

I did end up seeing the news yesterday in Reddit (I'm having issues getting the research tool to actually being used, tried to see if there was some recent changes) but it's unlikely that I was the only one who experienced modal the issue & if those didn't follow the tech news they could easily miss the change.