Like with most Google features, I don't see it yet. Recently, a tip was posted to HN that showed Google having a timer that could be activated by a search comma

Like with most Google features, I don't see it yet. Recently, a tip was posted to HN that showed Google having a timer that could be activated by a search command; another feature that simply doesn't work for me. I've tried both google.co.uk and google.com in Safari and Chrome. I also see the UI switching occasionally from the black bar at the top to the cleaner UI that's in the picture. Are they A/B testing or something? It makes Google feel very unreliable as almost nothing works consistently for me.