I potted up the second cutting that was grown in a jar of water. Those roots were about an inch long, and there were several. It will need TLC for a couple of weeks. The first still needs shade. It wilts slightly if left outside for more than a half day. I set it on the deck in the morning, which does not get direct sunlight then. One more forsythia cutting in water is sending out roots.
I don't know about the ones in potting soil. One made a root that came through the bottom of the pot. I sat it outside for a few hours and it wilted, badly. So back to the plastic bag mini greenhouse. It might survive.
So far it seems the water jar method is better than the potting soil method. Also, the thinner stem cuttings are rooting but the thicker ones are not, at least yet.
Left to right, forsythia cuttings still in water, freshly potted cutting in humidity tent, prior potted cutting - see last post, I think about two weeks.
Forsythia cuttings started in potting soil, still in their humidity tent.