Firefox Release Notes

Release Notes tell you what’s new in Firefox. As always, we welcome your feedback. You can also file a bug in Bugzilla or see the system requirements of this release.

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66.0.4
Firefox Release

May 5, 2019

Version 66.0.4, first offered to Release channel users on May 5, 2019

Fixed

unresolved

  • A small number of add-ons may be listed as unsupported or may not appear in about:addons. Their data is not lost; users should be able to re-install the add-ons and recover the data (Bug 1549129). More support information

  • If add-ons that use Containers functionality (such as Multi-Account Containers and Facebook Container) were disabled as part of this problem, any lost site data or custom configurations for those add-ons will not be recovered by this release. Users may need to set them up and login again in about:addons (Bug 1549204). More support information

  • Themes may not be re-enabled. Users may need to re-enable them in about:addons (Bug 1549022). More support information

  • Home page or search settings customized by an add-on may be reset to defaults. Users may need to customize them again in about:preferences or about:addons (Bug 1549192). More support information

  • Users with a master password set may need to enter or reset it for the fix in this release to take effect (bug 1549249). More support information

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