This was the first launch of the titanium fins. The BulgariaSat booster from two days ago was an older block 3 first stage with the "original" aluminum fins. They did glow quite a bit during the very hot re-entry, visible on the last few video frames before the feed cut out: https://youtu.be/Y8mLi-rRTh8?t=1405

That was probably not just glow. That was the shielding material actually burning.

Yes, you're correct. Elon stated in a tweet earlier today that the aluminum fins had burned up their ablative coating on every flight.

I misphrased it. I meant the second launch of the weekend. Not the second launch of the fins.

Your wording makes it sound like there have been two launches with the new grid fins. For clarification, I believe you meant the second of this weekend's launches was the first to use the new grid fins.