Here is what is new in Firefox 66.0.2

Martin Brinkmann
Mar 27, 2019
Updated • Mar 27, 2019

Mozilla is preparing the Firefox 66.0.2 release currently for the Firefox Stable release channel. The new Firefox version fixes crashes and a web compatibility issue with certain online services such as Office 365 or iCloud.

Firefox 66.0.2 has not been released yet but the new version will become available soon. Most Firefox installations will be upgraded to the new version automatically thanks to the build-in update functionality.

Firefox users may run manual checks for updates to download the update immediately after release.

Firefox 66.0.2

Firefox 66 introduced a major bug in Firefox that impacted several high profile online editors. We confirmed the issue last week in PowerPoint online. The editor would not accept any text input; while you could enter text, text that you added vanished immediately after focusing another element or a new line in the editor.

Mozilla uses the same workaround in Firefox 66.0.2. It enabled legacy keyCode and charCode for websites and services with issues to fix it for all users of the browser.

The official release notes confirm that users experienced the issue on Office 365, iCloud and IBM WebMail.

The Firefox preference dom.keyboardevent.keypress.hack.use_legacy_keycode_and_charcode lists the following sites currently that use legacy code: *,*,*,*,*,

You can add any site that is not listed to the value. Just add a comma to the end of the current value and type the address afterward. It is unclear if other sites are affected by the issue, however.

Firefox 66.0.2 fixes two crashes next to that:

  • A crash affecting Firefox on Windows 10 version 1809 when playing videos on YouTube. The crash affected the YouTube tab but not the browser itself.
  • A crash in Canvas with CreateBrushForPattern

Firefox users who are affected by these issues may want to upgrade the browser to the new version to fix these issues. The release is not critical for users who don't use these services.

Firefox 66.0.2 is the second minor update that Mozilla released after the Firefox 66.0 release in mid March.

Now You: Did you experience crashes or issues in online editors?

Here is what is new in Firefox 66.0.2
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Here is what is new in Firefox 66.0.2
The new Firefox 66.0.2 version fixes crashes and a web compatibility issue with certain online services such as Office 365 or iCloud.
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  1. Luke said on March 28, 2019 at 8:43 pm

    66.0.1 and 66.0.2 are disassociated from the O365 version of Word:

    The address wasn’t understood
    Firefox doesn’t know how to open this address, because one of the following protocols (ms-word) isn’t associated with any program or is not allowed in this context.
    You might need to install other software to open this address.

    This is getting annoying.

  2. Kubrick said on March 28, 2019 at 5:23 pm

    I am noticing a slight slow down with this version and some sites take forever to fully render notably facebook..i primarily use palemoon browser and it seems to handle facebook better.Not certain if noscript could also be an issue.

  3. badbanana said on March 28, 2019 at 1:53 pm

    minor, non security related updates like this should not be pushed. let it be an option.

  4. layla said on March 28, 2019 at 11:49 am

    after some minutes of the new firefox 66.0.2 appeared a Kaspersky Kis2018 pop up that notice me about a plugin called Googleupdate.exe ( googleupfateComRegisterShell64) that wants to install on firefox , why? I stopped the installation of that plugin

  5. AnorKnee Merce said on March 28, 2019 at 6:08 am

    So, the new FF 66 version introduced regressions that have to be fixed with FF 66.0.2. Something will usually go wrong when Mozilla upgrades FF every 6-weeks which is an exact copying of Google Chrome’s rapid upgrade schedule. This is because Mozilla Corp has much less resources than Google Inc.
    ……. It will likely be better for Mozilla to drop back to a quarterly or half-yearly upgrade schedule and not over-extend themselves.

    Since Mozilla Firefox likes to copy Google Chrome, maybe she should also follow M$ Edge and adopt the Blink engine of Google’s Chromium Project, ala Opera, Vivaldi, Brave, etc.

  6. Supergirl said on March 28, 2019 at 4:47 am

    Im taking a break from mainline Firefox….. Again…

    I use Waterfox & 60ESR

  7. bradam said on March 28, 2019 at 2:45 am

    I do not use these services, run Win8.1, have seen no issues but yes the 0.2 update has been pushed out to me already, installed. No problems as of yet, don’t anticipate any.

  8. anonymous said on March 28, 2019 at 12:48 am

    Firefox used to have the new tab page when set to blank to be black with the dark theme. Since Firefox 65, the new tab is white. Does anyone know if they are planning on fixing this?

  9. Andrew Kiernan said on March 27, 2019 at 8:43 pm

    Damn it… still no fix for av1 videos freezing the whole browser :-(

  10. Thorky said on March 27, 2019 at 6:36 pm
  11. anon said on March 27, 2019 at 5:38 pm
  12. Dave said on March 27, 2019 at 5:31 pm

    Has anyone figured out how to get the “DisableAppUpdate” policy working again after the 66 update? It worked in 65.

    “policies”: {
    “DisableAppUpdate”: true

    1. anon said on March 27, 2019 at 6:40 pm

      Make sure the indentation is correct, at least:

      "policies": {
      "DisableAppUpdate": true

      1. anon said on March 27, 2019 at 8:01 pm

        Never mind, it’s the comment system here that messes up the indentation.

      2. Dave said on March 29, 2019 at 1:15 am

        I rolled back to 65 now “Updates are disabled by your administrator” again ;)

  13. ULBoom said on March 27, 2019 at 4:03 pm

    Mozilla is winning the update race with MS! Will they get to one ver. 66 update every three days before Mar 31?

    Will the Evil Microsoft, never to be upstaged, buy Mozilla and drop them into shark infested waters never to be seen again?

    Stay tuned, same Bat Time, same Bat Channel!

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