print screen button not registering in firefox

[Ovidiu Alexa]

Open Firefox.
Add a breakpoint to a JavaScript code that listens to keydown or keyup and log the results.
Press the Scroll Button and you can see a log
Press the Pause button and you can see a log
Press the Prnt or PrtSc or Print Screen Button and you can see a white flash but no log result in the console.

The same happens in Chrome and Chromium

Works great on Ubuntu 16.

I didn't know what package to set this bug to so I had the onscreen keyboard package. This reproduces on a physical keyboard as well as the on screen keyboard.

Please help with solving this problem. If the answer involves changing the print screen button shortcut option to another key or do nothing, then this is not an option. This should work out of the box.

Thank you.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: onboard 1.4.1-2ubuntu1
ProcVersionSignature: Ubuntu 5.0.0-37.40~18.04.1-generic 5.0.21
Uname: Linux 5.0.0-37-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.9
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Mon Jan 6 16:58:09 2020
ExecutablePath: /usr/bin/onboard
InstallationDate: Installed on 2020-01-06 (0 days ago)
InstallationMedia: Ubuntu 18.04.3 LTS "Bionic Beaver" - Release amd64 (20190805)
InterpreterPath: /usr/bin/python3.6
Python3Details: /usr/bin/python3.6, Python 3.6.9, python3-minimal, 3.6.7-1~18.04
PythonDetails: /usr/bin/python2.7, Python 2.7.17, python-minimal, 2.7.15~rc1-1
SourcePackage: onboard
UpgradeStatus: No upgrade log present (probably fresh install)