BUG #16096: psql (non-interactive mode) SQL multi-request commands don't report all feedback ?!

The following bug has been logged on the website:

Bug reference: 16096
Logged by: Alain DE WIT
Email address: alaindewit(at)skynet(dot)be
PostgreSQL version: 12.0
Operating system: Centos 7.7.1908
Description:

When performing one INSERT SQL command in non-interactive mode I get a
feedback about the number of line inserted. OK
When performing the INSERT command SQL request following by for example a
select ; I don't get any feedback of the insert command !!??

NOT A BIG ISSUE !!

Example (screen-shot):
[adw(at)postgresql12 ~]$ psql -h 127.0.0.1 -U portefeuille -d portefeuille -c
"INSERT INTO ma_table ( SELECT 1, SUM(valeur) FROM ma_table WHERE classe =
2);"
INSERT 0 1
[adw(at)postgresql12 ~]$
[adw(at)postgresql12 ~]$
[adw(at)postgresql12 ~]$ psql -h 127.0.0.1 -U portefeuille -d portefeuille -c
"INSERT INTO ma_table ( SELECT 1, SUM(valeur) FROM ma_table WHERE classe =
2); SELECT * FROM ma_table WHERE classe = 1;"
classe | valeur
--------+--------
1 | 10
1 | 20
1 | 300
1 | 990
1 | 990
1 | 990
1 | 990
(7 rows)

Test enviroment (I'm new at Postgres but have more than 10 years
porfessional exeprience in Oracle):
-°) Centos 7.7.1908 runnig under VirtualBox version 6.0.10
-°) Postgres 12.0 installed from the yum Repository
-°) Putty
-°) postgresql.conf not modified

Regards