There is a feature in Safari called "Favorites" where users can assign certain sites to be a "favorite", which adds it as a tile on the newtab page, and also when focused on the location bar.

Since Firefox already has a "Top Sites" feature built in by default, it would be nice to show the same top sites in the awesomebar like Safari.

I have attached a screenshot of Safari's implementation.

This is basically the argument of one of the experiments we are already working on!