The Mozilla Foundation has made Firefox 58 files available for download on its official FTP servers. An official announcement will be made later today when the organization will also release the final changelog.
Firefox 58 marks the first major release since mid-November last year, when Mozilla released Firefox 57, a version that overhauled large parts of the Firefox codebase, including its old add-on system, with Mozilla choosing a new system based on the Chromium-compatible and standardized WebExtensions API.
These changes have continued two months later, in today's Firefox 58 release. Except for a few changes to Firefox's settings panel, most of the new Firefox features are under the browser's hood.
For example, Firefox 58 comes with a new feature called Off-Main-Thread painting, which are improvements to Firefox's built-in graphics engine.
On the UI side, Firefox 58 includes support for auto-filling credit card details, a feature that users can disable or enable from the Privacy section of the browser's settings panel.
Changes have also been made to the Firefox screenshot tool, which can now copy-paste screenshots directly to the OS clipboard, and the screenshot tool (aka Firefox Screenshots) now also works in Private Browsing mode.
Firefox 58 is also the version where Mozilla scheduled to block user fingerprinting attempts via the HTML5 canvas element. More details are available here.
Engineers also rolled out a security-related change: Firefox 58 being the first Firefox version that blocks users from accessing "data:" URLs in certain conditions, to safeguard users from a well-known phishing attack scenario.
Article updated with link to official announcement.