This falls under the category of 'annoyance' and I am looking for an explanation of what is happening:
Firmware Name: RepRapFirmware for Duet 2 WiFi/Ethernet
Firmware Electronics: Duet WiFi 1.02 or later + DueX5
Firmware Version: 2.04 (2019-11-01b1)
WiFi Server Version: 1.23
Web Interface Version: 1.22.6
Running on an Linux Ubuntu laptop and using the scroll pad on the laptop
When I go to 'Settings' - 'System Editor' - and I double click on config.g, about half the time when the system opens up config.g I can scroll up and down using the scroll pad (two finger motion sliding fingers up or down on the pad). The other 50% of time the two finger scrolling doesn't do anything and I have to click and drag the window bar (?) on the right to get to the place where I want to edit the config.g file.
When I say 'window bar', I mean the black vertical line on the right side of the window that represents the section of the file that is being displayed on the screen out of the entire file (ie when the window shows about half the file's content, this bar is about half the height of the window. Bigger files produce a smaller (scroll?) bar.
As I said, just an annoyance that I have been putting up with for a long time but thought 'hey, I wonder ....'
I loaded things up in Chrome and things work perfectly there. Thanks for helping me figure out the cause !