BUG #15620: pgAdmin IV pgAgent multi-schedule jobs messed up view of schedules

The following bug has been logged on the website:

Bug reference: 15620
Logged by: Basil Hararah
Email address: bhararah(at)hotmail(dot)com
PostgreSQL version: 11.1
Operating system: Windows 10 x64
Description:

Dear Madam / Sir

First of all I would like to mention that this bug was not encountered in
pgAdmin III 1.22 unlike pgAdmin IV which no version of it, from 1.0 up to
4.1, could handle this issue properly.
I also tried many versions of PostgreSQL with no luck in getting this
solved.
I could only try this using pgAgent 3.4. I could not install pgAgent 4.0
because for some reason it does not appear on the Stack Builder installer
and I could not find another way to install it on Windows 10 x64.

The issue can be encountered when a job is created with more than one
schedule.
You will notice that Properties tab shows correctly if you click on the 1st
schedule in schedules list of the job but if you click on any other
schedule, like 2nd or 3rd etc., Properties tab will keep showing the 1st
schedule properties all the time.
A fresh installation of pgAgent was used on a server that did not have
pgAgent before and the same issue was encountered which confirmed that this
issue is a software bug issue not a messed up settings issue on my side.

Looking forward to hearing from you.
Thank you for your time and efforts.

Best regards,
Basil Hararah