BUG #15702: Bug in pgadmin 4.3 for tables with json columns

The following bug has been logged on the website:

Bug reference: 15702
Logged by: Pål E Megaard
Email address: pempost(at)gmail(dot)com
PostgreSQL version: 11.1
Operating system: windows
Description:

Output of columns of type json seems not to work.

SELECT normal_column FROM table
Runs fine

SELECT * FROM table (or SELECT json_column FROM table)
Outputs: "Not connected to the server or the connection to the server has
been closed."
But the notification window flashes the correct "Successfully run. N rows
affected" for a second or two.

I did not have this problem with pgadmin 4.2 or 4.1. Note that columns of
type jsonb still works fine.

Data from "help".
Version
4.3
Copyright
Copyright (C) 2013 - 2019, The pgAdmin Development Team
Python Version
3.6.5 (v3.6.5:f59c0932b4, Mar 28 2018, 16:07:46) [MSC v.1900 32 bit
(Intel)]
Flask Version
0.12.4
Application Mode
Desktop
Current User
pgadmin4(at)pgadmin(dot)org