Why settle for a basic build of your Firefox browser on Windows Operating Systems when you can have one that performs 25% faster? Mozilla does not provide optimized browser packages for Windows, while many Linux ("from scratch") users get the advantage of a browser built specifically for their system. That needs to change! So, here is the Pale Moon project: Custom-built and optimized Firefox browsers for Windows Operating Systems. Make sure to get the most speed out of your browser.

Of course, getting a faster browser is not just about optimizing the compilation process (building a program from its source code), but also about carefully choosing features and how to choose the best setup. This means that this browser, however extremely close to Firefox, does not have all the functions that Firefox has. A few, carefully selected, features have been disabled that are not in high demand, and that do not interfere with the way web pages are displayed or function; all to maximize speed and efficiency of the browser. Please see the page with technical details to learn exactly what the browser supports, and what it doesn't support. In short, if you need accessibility features or parental controls, then please visit the firefox homepage and get the official, non-optimized build.

Features

  • Highly optimized for current processors
  • 100% Firefox sourced: As safe as the browser that has seen years of development.
  • Uses slightly less memory because of disabled redundant and optional code
  • Significant speed increases for page drawing and script processing
  • Support for SVG and Canvas
  • Support for Firefox extensions, themes and personas

What's New

Changes/fixes:

  • Fixed wrong color of decoded JPEG-XL images.
  • Fixed and issue with plugins not receiving keypress events properly.
  • Added support for the JPEG-XL image format.
  • Implemented regular expressions lookaround/lookbehind.
  • Aligned CORS header parsing with the updated spec. See implementation notes.
  • We no longer fire keypress events for non-printable keys. See implementation notes.
  • Added support for MacOS 13 "Ventura" in the platform, primarily benefitting White Star.
  • Fixed potentially problematic thread locking code on *nix platforms.
  • Fixed some small issues in the display and operation of the Web Developer tools.
  • Removed unused but performance-impacting panning and tab animation measuring code. (telemetry leftovers)
  • Improved code for SunOS builds.
  • Updated Internationalization data for time zones.
  • Fixed a buffer overflow for Mac builds.
  • Security issues addressed: CVE-2022-45411 and potential issues without a CVE number.
  • UXP Mozilla security patch summary: 2 fixed, 1 DiD, 1 deferred, 25 not applicable.

Implementation notes:

  • CORS support has been updated to the current spec. Most importantly, Pale Moon now accepts wildcard entries ("*") for the CORS statements Access-Control-Expose-Headers, Access-Control-Allow-Headers and Access-Control-Allow-Method. Note that wildcards are ignored (according to the spec) when credentials are passed.
  • Pale Moon will no longer fire the keypress events in content when the key pressed is a non-printable key. This is in response to issues where webmasters would use rudimentary and naïve input-restricting scripts in onkeypress handlers that would not take into account editing keys or navigation keys, causing issues for users trying to enter data into forms (and e.g. finding they could no longer use backspace, cursor keys or tab). This aligns our behavior with other browsers for web compatibility, although it should be considered a website error expecting not all keypresses to be intercepted in keypress events.