I just ran into the issue, create new project from the ground, copied old code from a project of some months ago (working flawlessly in old code) and it just don’t work, debug info doesn’t throw anything interesting…
Downgrading to ~2.3.1 with the same version of sage also does the trick.
There’s something seriously wrong around here…
Mac OS 10.15.6
Yarn 1.22
Node 12.18.3
Sage 9.0.10