Jerry Seinfeld is back with a new Netflix special, “23 Hours To Kill,” recorded last October. Martha and I saw him on that tour, so much of the material in the special isn’t new to us, but like an old episode of “Seinfeld,” it’s still fun to watch.

Among the topics Jerry covers: smartphones and those ghosty dots you get when someone you’re texting with is composing a reply. Automobile air vents and dual-zone controls. Spring tension on portable toilet doors and public restroom architecture. Going out for the night, friendships, and the differences between marriage and single life. The latter fills up the last third of the special and doesn’t cover ground dozens of other comics have touched on previously, but it does suggest that the one domain in which control-freak Seinfeld is not in charge is his own home.

Seinfeld also did his Pop Tart routine, which he constructed and added to his act seven or eight years ago. At the time, I knew Paula Poundstone to be the only comic with a good bit about Pop Tarts (watch it here), so I asked her what she thought of Seinfeld encroaching on her comedic ground. You can listen to her response — and the whole conversation — here.

Don’t get me wrong. Seinfeld is still a pleasure to watch and remains one of the best comedians of his generation. He’s still a brilliant wordsmith, constructing each chunk of his standup to work in a certain rhythm, with every syllable placed perfectly. He clearly loves performing live, and will no doubt return to the stage whenever we’re comfortable gathering in large groups to listen to him. But this was the first time I noticed him raising his voice a lot, as if he’s pushing harder to try to make the jokes work better (a la Jay Leno). And I detected a tinge of bitterness that goes beyond simple guy-over-sixty crankiness.

I wonder whether he’ll produce any more episodes of “Comedians in Cars Getting Coffee.” He’s done six seasons, all of which are on Netflix, but hasn’t said a word about doing another. Perhaps he’s already interviewed all of his friends in comedy and doesn’t feel like stretching beyond that circle.

That would be too bad. But in a world where we all have a lot of hours at home to kill, at least we can spend this hour laughing out loud with Jerry.