There is also a new system called JavaScript Startup Bytecode Cache (JSBC) to reduce the launch and integration time of WebRender, a website rendering engine originally used for Mozilla Servo.
Firefox 58 supports auto-fill credit card information, users can turn on or off in the Privacy section of the settings.
Enable / disable auto-fill credit card information on Firefox
Screen capture tool (Firefox Screenshots) can now be copied - pasted to the OS clipboard and runs in an incognito mode.
Firefox 58 is also the version that Mozilla plans to block user fingerprints with HTML5 canvas elements.
In terms of security, Firefox 58 is the first Firefox version to block users from accessing URL 'data' in certain situations to protect users from phishing attacks.
You read Firefox 58 here.
Here are other features and improvements of Firefox 58 https://hacks.mozilla.org/2018/01/firefox-58-the-quantum-era-continues/
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