Mozilla added an option to the about:config page of Firefox Stable that allows users to list only modified preferences. The organization launched the option in
Firefox Nightly in February 2021 initially.
Firefox's about:config page can best be described as a treasure trove for users who want to modified browser preferences that are, for the most part, not displayed in the user interface options.
The configuration enables Firefox users to customize the browser heavily, for instance by enabling new features early or disabling unwanted features. The use of configuration files improves this further.
Modified preferences are displayed in bold on the about:config page, but there was no option until now to display only those using an option provided by Mozilla. While it is possible to use an hack using the Web Console of the Developer Tools
to display only modified preferences, it is far from ideal and only a niche option.
Mozilla did launch a redesigned about:config page in Firefox 71, but it lacked some of the features of the previous version, including the ability to use
deep links to preferences or sorting options.
When you open the about:config page in Firefox Stable right now, you will see an option to display only modified preferences. We tested this in Firefox 87 Stable, the latest version at the time of writing, and the option is there.
