I tested again this morning to collect details, and it's working fine !!?? whereas I spent 1-2 hour the 6 nov with this precision pb, before to test on pgsql...
sorry :(
it's may be linked to the "big" Windows update of last week partially completed before I restart my computer a 2nd time this WE.
Windows 10 Pro
Firefox 82.0.2 64Bits
PostgreSQL 12.4 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-39), 64-bit