http://screenrant.com/star-trek-discovery-tribbles-history-easter-egg/

The cute, fan-favorite classic Star Trek alien makes its debut in Star Trek: Discovery. Find out the history of the troublesome Tribble.

It must've been the second one or even part of the pilot episode since I wasn't able to DVR the whole thing unless you know something about a future episode that I don't. I thought this would be a list of all the tribble appearances so far that fans have been able to see with ease, which are the first one with Kirk, the cartoon episode, a Deep Space Nine episode where Worf says why Klingons hate them so much, which is because they're considered by Klingons to be an ecological menace, and one of the movies. The pilot was a confusing one for me because there was no involvement with the title vessel and an unexpected new look for the Klingons. Are they gonna start saying there are several species of them like there are with the Xindi? I had trouble following the plot itself and found it confusing. The technology itself consists of wishful thinking that would only be doable if God created parallel worlds like the string theory dimensions talk about, which is why I brought it up in a thread. The starships look neat including the alien ones like Borg ships; but again, that's probably wishful thinking. I don't suppose they got into an explanation about the dude with the implant, did they? He almost looks like he may have been a victim of a Borg attack, which is feasible since they didn't make Starfleet aware of how fast they can travel when Archer encountered them. The nerve pinch, which was originally introduced in a Doctor Who episode, working the way it does on the show is only theoretically if parallel universes are out there.
Take care and God bless