Version 58.0, first offered to Release channel users on January 23, 2018
Thank you to all of the new Mozillians who contributed to this release of Firefox!
User profiles created in Firefox 58 (and in future releases) are not supported in previous versions of Firefox. Users who downgrade to a previous version should create a new profile for that version. Learn about alternatives to downgrading on our support site.
Users running Firefox for Windows over a Remote Desktop Connection (RDP) may find that audio playback is disabled due to increased security restrictions. Learn how to mitigate this issue until it is corrected in an upcoming release.
Users running certain screen readers may experience performance issues and are advised to use Firefox ESR until performance issues are resolved in an upcoming future release
When using certain non-default security policies on Windows (for example with Windows Defender Exploit Protection or Webroot security products), Firefox may fail to load pages (bug 1433065).