The notification window at bottom right corner is pesky. Is it possible to disable it?
Changing the value in Query info notifier timeout to
-1 it will disable it. This is documented in the official pgAdmin documentation in the Preferences Dialog help as:
Use the Query info notifier timeout field to control the behaviour of the notifier that is displayed when query execution completes. A value of -1 will disable the notifier, and a value of 0 will display it until clicked. If a positive value above zero is specified, the notifier will be displayed for the specified number of seconds. The default is 5.
There is no option to disable it.