Firefox 52 Nightly: plugin support (except Flash) dropped

Martin Brinkmann
Oct 6, 2016

If you run Firefox Nightly, currently at version 52, you may have noticed that plugins that you may have used in the past are no longer supported in the browser.

So-called NPAPI plugins such as Java, Silverlight or Flash are on their way out. While the time frame varies browser by browser, all major browser developers announced the end of NPAPI support.

Mozilla did so about a year ago on October 8, 2015 stating that plugins were the source for performance, crash and security incidents.

The organization published a schedule recently that details when support for NPAPI plugins end in Firefox.

The first Firefox version to ship without support for NPAPI plugins by default -- except for Adobe Flash -- is Firefox 52.

Mozilla plans to ship that version with an override that allows you to turn support back on in Firefox 52. This override is removed from Firefox 53 however, and the only Firefox version with support for NPAPI plugins onward is Firefox 52 ESR.

Firefox 52: end of NPAPI

firefox 52 no plugins

The end of NPAPI in Firefox 52 affects all plugins except for Adobe Flash. Flash is still widely used, and the chance is high that this won't change in the coming six months.

Note: You may still see content listed under plugins, namely Content Decryption Modules or Video Codecs. These don't use NPAPI and will continue to work just fine in Firefox.

Eventually though, Flash NPAPI support will also be removed from Firefox. This may coincide with Mozilla bringing Pepper Flash, the same that is used by Google Chrome, to Firefox.

First, lets take a look at the timeline of events:

  1. March 7, 2017 -- Firefox 52 and Firefox 52 ESR are released. All plugins but Flash are disabled by default. Mozilla Firefox users may flip a preference switch to enable support for non-Flash NPAPI plugins in Firefox 52. Firefox 52 ESR will support plugins throughout its lifecycle (until Firefox 60 ESR is released). Firefox users may flip the preference plugin.load_flash_only to false to re-enable support for other NPAPI plugins.
  2. April 18, 2017 -- The release of Firefox 53 marks the end of NPAPI plugin support in Firefox. The override preference is removed. Flash is the only plugin left standing.
  3. First half of 2018 (May) -- Firefox 60 ESR is released.

So, Enterprise customers and users who rely on plugins may switch over to Firefox 52 ESR for the time being to extend support for another year.

Starting today, new profiles that you create in Firefox 52 Nightly will block all plugins but Flash from being used by the browser. From tomorrow onward, this will also be the case for existing Firefox profiles.

You can track the removal of NPAPI support on Bugzilla. (via Sören Hentzschel)

Firefox 52 Nightly: plugin support (except Flash) dropped
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Firefox 52 Nightly: plugin support (except Flash) dropped
If you run Firefox Nightly 52, you may have noticed that plugins that you may have used in the past are no longer supported in the browser.
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  1. MasterCATZ said on March 12, 2017 at 5:45 am

    can not get flash v25 working with FF 52 or FF 53 … on ubuntu 16.1

  2. ConstantuS said on October 16, 2016 at 11:56 am

    Firefox Nightly x64 crashes after clear install on new system (((

  3. Heimen Stoffels said on October 15, 2016 at 12:05 pm

    And Firefox isn’t the only one. Web (formerly Epiphany) for Linux also dropped plugin support on the current Git version:

  4. Bah Humbug said on October 8, 2016 at 5:01 pm

    Nuance Dragon NaturallySpeaking 13 and PDF X-Change Editor 6 both use Firefox plugins and are under threat then? Those are very popular programs!

    1. Martin Brinkmann said on October 8, 2016 at 6:08 pm

      Yes they won’t work anymore when the change hits.

      1. Bah Humbug said on October 8, 2016 at 7:12 pm

        Hi Martin, thanks for sharing all your knowledge by the way, I’ve been reading all of your RSS feed articles for over a year now and I have learned a lot from them.

      2. Martin Brinkmann said on October 8, 2016 at 8:14 pm

        That’s great, glad that you find (some of) my articles useful.

  5. Chryss said on October 7, 2016 at 4:56 am

    So this only affects things listed under plugins, not extensions?

    Alright, so if there’s no more Java, that means NoScript becomes obsolete? I can’t imagine running without it for security/blocking garbage. Or am I misunderstanding something?

    And am I now forced to use that DRM checking open 264 thing instead of my VLC plugin?

    1. Parker Lewis said on October 7, 2016 at 11:56 am

      ” And am I now forced to use that DRM checking open 264 thing instead of my VLC plugin? ”

      Yes, but it’s likely more secure than the VLC plugin since it’s more focused and tightly sandboxed. (I’m saying this as a VLC fan)

      I don’t have the VLC plugin and disabled the OpenH264 plugin, but there has only ever been one instance where I couldn’t play a video. It was a live TV broadcast during the Euro 2016. In my experience the website will provide you with a video format you can play unless there’s big money involved :)

      Netflix might be an exception, I don’t use it so I wouldn’t know.

    2. Martin Brinkmann said on October 7, 2016 at 6:20 am

      Chryss, NoScript is not affected by the removal of Java from the browser. What you mean is JavaScript, which is something entirely different.

      1. Parker Lewis said on October 9, 2016 at 4:18 pm

        You won’t miss Foxit Reader. The main purpose is to read PDF files inside Firefox, but Firefox has had a built-in functionality for that for some years now. Sometimes a website forces a PDF to be download-only. I don’t know if Foxit Reader obeys this directive, the built-in reader does. Java plugin can be ditched with no remorse.

        For extensions it’s not as clear cut. There are two areas where they need to be compatible, WebExtensions and e10s. Compatibility with WE implies compatibility with e10s, but the opposite is not true.

        In your list, and regarding WebExtensions compatibility:
        Will be compatible: ABP, NoScript, RequestPolicy
        Should be compatible: Tab Mix Plus, No Resource URI Leak
        I’d guess that HTTPS Everywhere will be compatible as well because it is related to Tor, which Mozilla cares about.

        The rest I don’t know, you can either wait or ask the authors on AMO.

        For e10s compatibility you have this:

        Not a complete answer but things are still being discussed when it comes to add-ons, so it’s harder to predict ^^

      2. Chryss said on October 8, 2016 at 9:00 pm

        Oh, that’s so great of you! The only plugin other than video stuff, java and flash that I have is the Foxit Reader plugin. Extensions I have, which are my bigger concern, are:

        1. Adblock plus with Element Hiding Helper and Customizations for ABP
        2. EPUB Reader
        3. No Resource URI Leak
        4. NoScript
        5. Privacy Badger
        6. Request Policy
        7. Right to Click
        8. Self Destructing Cookies
        9. Tab Mix Plus
        10. The Addon Bar (restored)
        11. HTTPS Everywhere

        Any help would be appreciated. Thanks!

      3. Parker Lewis said on October 7, 2016 at 7:27 pm

        Definitely not mocking you, you even understood there was some information missing. If even self-learning out of curiosity can be mocked, what’s left to be praised ?

        Maybe we can help. Which plugins do you have and which ones do you know you need ?

        You should be fine without VLC Plugin if all you’re doing is watching videos. If you have a plugin from your antivirus vendor, they’ll figure out what to do before Firefox removes support. Other than that, unless you use the web in unusual ways chances are very high that you don’t need any other plugin but Flash.

        (OpenH264, Google Widevine and Adobe Primetime CDMs are special, keeping them enabled or not should be a separate choice)

      4. Chryss said on October 7, 2016 at 4:09 pm

        Yeah, I definitely don’t claim to be an expert on any of this, which is what makes all of this so frustrating. As a non-technical person, I have still tried to educate myself as best I can. I’ve tried to make smart choices with regards to security and privacy, and to keep my system running smoothly. I managed to avoid the win 10 upgrade nag, and haven’t had a virus or malware problem in years. I’ve spent countless hours reading sites like this one and doing research on software etc.

        But at some point those of us who aren’t tech people get stymied by the jargon (like NPAPI) or concepts that require more advanced knowledge to understand. I worked hard to get an FF browser that was both secure and running well, while still giving me the functionality I wanted. Then it comes out that some of that effort might now be useless, and I will have to spend yet more time trying to get a handle on those changes and finding new fixes/plugins/what-have-you. I’m often left with the feeling of ‘I know enough to know there’s a problem, but not enough to know exactly what the problem is or how to fix it.’

      5. Parker Lewis said on October 7, 2016 at 11:25 am

        Ha, I like this mistake. Whenever you notice that someone who claims to be competent doesn’t know the difference between Java and JavaScript, you know he is a massive fake. Of course I’m not talking about you Chryss. For instance I once met a professor of a reputed 8000€/year school teaching web technologies who did not know this.

        Another even more reputed school moves most of the money from students upwards to a different structure, going around State rules using a lame trick. They push students into debt but most of the money is not used to run or improve the school, it’s just a make-money scheme for the mother company, yes, even if like in this case the school is registered as a non-profit organisation, because lame tricks. But I’m completely off topic :)

      6. Chryss said on October 7, 2016 at 6:25 am

        Thanks, Martin. This stuff can get so confusing for those of us who maybe know more than the average user but are by no means tech gurus.

  6. Wayne J. said on October 7, 2016 at 3:53 am

    Not sure of Google Talk Plugin and Java Applet Plugin. Will they be gone too? If yes will there be any non-NPAPI replacements?

    1. Martin Brinkmann said on October 7, 2016 at 6:21 am

      If they use the NPAPI interface, which they do I think, they won’t be supported anymore.

  7. Jimmy James said on October 7, 2016 at 12:11 am

    Gone in a flash! I hope it never comes back!!! Such an insecure program…visit a website, bang you’re infected with an Encryption virus. Thanks Flash!

    1. Parker Lewis said on October 7, 2016 at 1:43 am

      Or thank you ad networks, rather.

  8. Ad0be CE0 said on October 6, 2016 at 8:54 pm

    Good Luck. Adobe seems like too-big to me to just let Flash fail.

  9. pd said on October 6, 2016 at 8:01 pm


    But get rid of that Flash shit as well!

  10. wolf said on October 6, 2016 at 7:16 pm

    I’m sorry, I’m not computer savy.

    What does that mean for all the browser games, which use flash? Can they somehow be coverted so that FF can handle them?

    1. Martin Brinkmann said on October 6, 2016 at 7:27 pm

      Flash is still supported after Firefox 52.

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