Animation Python track neither saved in python state, nor in Trace

In animation view, Python tracks are not saved in python state file and not tracked by the python trace.

start Trace with All Properties and Fully trace supplemental Proxies
Create a python track
stop trace -> python track does not appears
save as python state, with All properties and without Skip options -> python track does not appear
save as pvsm -> python track is written

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information