How to prevent Firefox log messages in Jenkins output console?

Question

I am using selenium.NET webdriver with nunit to run automated tests.

When I run tests under Jenkins (this problem does not occur when it does not work under Jenkins), I get many Firefox debug messages printed on the Jenkins console, for example:

1449667715916   addons.manager  DEBUG   Application has been upgraded
1449667715929   addons.manager  DEBUG   Loaded provider scope for resource://gre/modules/addons/XPIProvider.jsm: ["XPIProvider"]
1449667715931   addons.manager  DEBUG   Loaded provider scope for resource://gre/modules/LightweightThemeManager.jsm: ["LightweightThemeManager"]
1449667715934   addons.manager  DEBUG   Loaded provider scope for resource://gre/modules/addons/GMPProvider.jsm

I believe that the reason is that Jenkins catches stdout from the program I run and the processes it created (the Firefox process is created by the selenium webselener).

How can I stop these error messages from appearing?

Possible solutions that I could think of (I could not find a way to reform any of the below):

• Prevent Firefox from printing its journal messages on its stdout
• Catch Firefox stdout in a file.
• Make Jenkins ignore the process logs.