Log Message:
Update to 66.0

Changelog:
New
    Firefox now prevents websites from automatically playing sound. You can add \ 
individual sites to an exceptions list or turn blocking off. To learn more about \ 
block autoplay, which will be rolled out gradually to all users, visit the \ 
Mozilla blog.

    Improved search experience:
        Find a specific webpage faster when you have a lot of tabs open: You can \ 
now search within all of your open tabs from the tab overflow menu
        Easier search via a redesigned new tab in Private Windows

    Smoother scrolling: Scroll anchoring keeps content from jumping as images \ 
and ads load at the top of the page

    Improved performance and better user experience for extensions:
        Extensions now store their settings in a Firefox database, rather than \ 
individual JSON files, making every site you visit faster
        A redesigned keyboard shortcuts section in about:addons makes it easier \ 
to view and adjust default shortcuts

    Redesigned certificate error pages help you better understand and resolve \ 
issues, including identification of certificate issuers for anti-virus software

    Added basic support for macOS Touch Bar

    Experimenting with an improved Pocket experience in New Tab with different \ 
layouts and more topical content

    Improved performance and reduced crash rates by [doubling web content \ 
loading processes from 4 to 8 [1]

    Easier, passwordless security: Added support for Windows Hello on Windows \ 
10, allowing you to use your face, fingerprint, or external security keys for \ 
website authentication

Fixed
    The Dark and Light Firefox themes now override the system setting for title \ 
bar accent color on Windows 10

    Linux users: Resolved an issue that caused Firefox to freeze when \ 
downloading files

    Various security fixes

Changed

    System title bar is hidden by default to match Gnome guideline for Linux users

Developer

    DevTools Inspector is now fully usable when the Debugger is paused

    Lowered priority of setTimeout and setInterval during page load to improve \ 
overall page load performance

    Fixed: <button> element is no longer special cased in event dispatch, \ 
per latest specifications

Security fixes:
Not available yet.