Аннотация:AT2020qvn During Fermi GRB 200803B inspection (Fermi GCN #28201, Lipunov et al. GCN #28208, GCN #28204), started 27 sec after notice time (55 sec after trigger time) at 2020-08-03 16:53:38 UT with upper limit up to 18.6 mag, we found possible optical counterpart , see cover map and OT position MASTER-SAAO auto- detection system ( Lipunov et al., “MASTER Global Robotic Net”, Advances in Astronomy, 2010, 30L ) discovered OT source at (RA, Dec) = 14h 46m 03.45s -41d 31m 56.7s on 2020-08-03.70644 UT. The OT unfiltered magnitude is 17.9m (mlim=18.1).