This guide offers information on changes made to the Firefox 55 preferences, as well as new, deprecated, or removed Ghacks user.js preferences.
Mozilla released Firefox 55.0 to the Release channel on August 16, 2017. The new version of Firefox improved session restore on startup significantly, but is also incompatible with older versions as profile data changed.
Note: The Ghacks user.js file is a large well maintained file that lists Firefox preferences and values that are considered safer or better for privacy. You can check it out on the official project site. If you never worked with a user.js file before in Firefox, make sure you read the excellent overview to understand how it works.
Thanks goes to Earthling, Pants and anyone else who contributed to the list this month.
Note: You may access the full Firefox 54 to 55 diff here. This is important information for users who already use the user.js file as it highlights new, removed, and changed preferences. It is recommended that you go through the listing and add the preferences to your current one that you require.
In total, there were 432 recorded diffs between Firefox 55.0 and Firefox 54.0. 207 of those are new, 66 removed, and 159 different.
New preferences in Ghacks user.js for Firefox 55:
New preferences that are commented out by default:
Newly activated preferences that were commented out previously:
Commented out preferences:
Changed values of active preferences:
Removed from user.js:
If you have questions about any of those preferences, remarks, or a comment, feel free to leave a comment below or head over to the project on GitHub to leave comments there.
Ghacks is a technology news blog that was founded in 2005 by Martin Brinkmann. It has since then become one of the most popular tech news sites on the Internet with five authors and regular contributions from freelance writers.