Release of Firefox version 127

Held web browser release Firefox 127 and the update is generated branches with long term support – 115.12.0. On stage beta testing translated Firefox 128 branch, scheduled for release on July 9.

Basic innovations V Firefox 126:


  • A button has been added to the “V” menu with a list of all open tabs and to the tab's context menu to close all duplicate tabs in the current window.
  • Automatic replacement of the HTTP protocol with HTTPS is enabled for resources in the ‹img›, ‹audio› and ‹video› tags, if these tags are used on a page opened via HTTPS. If downloaded resources are not available via HTTPS, they will no longer be displayed from pages opened via HTTPS.
  • Added support for proactively determining host IP addresses without waiting for the user to follow a link or request a resource specified on the page. Domains that need to be resolved in advance in DNS should be listed through the “link” element with the ' attributerel=”dns-prefetch”'.
  • To reduce information that can be used to indirectly identify users, for 32-bit x86 systems the User-Agent header, as well as the navigator.platform and navigator.oscpu JavaScript APIs, will now indicate the x86_64 architecture.
  • The screenshot tool now supports creating screenshots for SVG and XML files, as well as for service “about:” pages. Added the ability to control the creation of screenshots using keyboard shortcuts, implemented compatibility with design themes and display mode with high contrast (HCM, High Contrast Mode). Improved performance for saving large areas of the screen.
  • In about:config added settings toolkit.scrollbox.pagescroll.maxOverlapPercent and toolkit.scrollbox.pagescroll.maxOverlapLines, allowing you to change the page offset when scrolling, specified in percentages and lines.
  • On Windows platform implemented the ability to automatically launch Firefox after the computer boots. Thanks to preloading, the user does not have to wait when launching the application for the first time – the browser will be ready to work instantly. The mode is enabled in the General/Startup settings section or through a notification displayed similar to the invitation to use Firefox as the default browser.
  • On macOS and Windows platforms, additional access protection is provided when using AutoFill for saved passwords or when viewing password information in a password manager. Such operations with a password manager will require confirmation of authentication on the system (for example, entering a system password, fingerprint verification, voice or face authentication).
  • On the macOS platform, tab navigation is enabled by default, rather than using the macOS-specific keyboard navigation mode, which is inconsistent with behavior on other platforms (you can revert to the old mode in Settings).
  • In texts for which the format is used WebVTT (Web Video Text Tracks Format), added support characters, valid in HTML markup. WebVTT is used to organize text output at certain points in time, for example, to display subtitles.
  • In API Clipboard interface is enabled by default ClipboardItem and support for the and navigator.clipboard.write() methods, which allow a web application to read and write data to the clipboard. If you try to read data from the clipboard that was not written by the current web application, the user will be prompted to confirm the action before performing the operation.
  • Implemented experimental support for setting symmetrical letter spacing via a CSS property letter-spacing. In the new mode, the interval is not set between the current and next symbol, but is divided into two parts, which are applied before and after the symbol. The mode is enabled via the layout.css.letter-spacing.model setting in about:config.
  • The “href” attribute of the “‹base›” tag, used to set the base path for relative links, does not allow the use of the “data:” and “javascript:” schemes.
  • In gradients created with the CSS functions conic-gradient(), linear-gradient(), radial-gradient(), repeating-conic-gradient(), repeating-linear-gradient() and repeating-radial-gradient() , allowed to use type “‹color-interpolation-method›“.
  • To object Setwhich defines a collection of values, methods have been added that implement typical operations with sets: Set.prototype.intersection(), Set.prototype.union(), Set.prototype.difference(), Set.prototype.symmetricDifference(), Set.prototype .isSubsetOf(), Set.prototype.isSupersetOf() and Set.prototype.isDisjointFrom().
  • Prohibited installation of add-ons whose XPI files are signed using unsafe algorithms (the PREF_XPI_WEAK_SIGNATURES_ALLOWED setting is set to false by default).
  • IN versions for the Android platform:
    • Added support for translating content from one language to another. As in the desktop version of Firefox, translation uses a translation system built into the application, which performs translation on the user’s local system without accessing external cloud services.
    • A new item “Passwords” has been added to the “…” menu.
    • Allowed the use of the Enter key on the side number pad of desktop keyboards to confirm the URL entered in the address bar.
    • Additional optimizations were included at the compilation stage, which made it possible to increase the responsiveness of the interface, reduce startup time and extend the battery life of the device.
    • The section with a list of recently saved pages has been moved to the bookmarks section. List items no longer disappear after expiration.

In addition to innovations and bug fixes, Firefox 127 has been fixed 22 vulnerabilities. 11 vulnerabilities are marked as dangerous, of which 9 are caused by memory problems, such as buffer overflows and access to already freed memory areas. Potentially, these problems can lead to the execution of an attacker's code when opening specially designed pages.

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