So this morning I took another vid at -22 C, but it didn't stall. RPMs seemed low for a normal start, but it held pretty steady.
We'll see what it does tomorrow.
I've always used Shell 91, but from quite a few different stations. I'm pretty sure it's not a fuel quality thing.
But no CELs or any sort of lasting issue. Runs great otherwise so I'm not going to lose any sleep, but I will take some more vids so I can follow up if needed.