That didn't take long. I spent a couple of hours on circuit.io, which looks like it is not Autodesk Circuits. It was sort of OK, sort of meh. But when I got to creating a schematic symbol from scratch ... that was a dealbreaker:
They give you a handful of drawing tools, but the tools have no idea they are drawing schematic symbols (except for the "pin" menu item). Once you put something onto the editor page, you're not going to change it much. You can select it, and then you see a small context-sensitive form along the bottom. Would you like to move a part? No problem, just select it and then fill in the appropriate X/Y coordinates. If you want to move several parts, do each of them individually. The part I need to make has 26 pins, but it's not a DIP.
There certainly might be an friendlier way to do that, but I didn't discover it. (Large swaths of the site look like they haven't been touched since 2015, so I'm not optimistic about improvements.)
Anyhow, I'm back on upverter.com. I still don't remember why I left.