Firefox 54.0 Features:
- Added Burmese (my) locale
- Added support for multiple content processes (e10s-multi)
- Simplified the download button and download status panel
- Various security fixes
- Moved the mobile bookmarks folder to the main bookmarks menu for easier access
- Additional changes for web developers
- Added ability to create and save custom devices in Responsive Design Mode
How to Upgrade Firefox in Ubuntu:
Ubuntu is publishing the latest Firefox release packages through the security & updates repositories.
Make sure you enabled the repositories via Software & Updates utility.
Depends on the building process, there may be a time delay for publishing Firefox 54.0. Check the launchpad build page.
Once the new packages are well tested and published, you’ll receive the updates via Software Updater: