Mozilla needs to improve support for add-ons

Martin Brinkmann
Jan 5, 2015
Updated • Jan 5, 2015

I'm currently rewriting and updating articles here on this site that were published years ago. Currently working on the email category which had its fair share of Thunderbird extension reviews.

At least half of the extensions reviewed back then are no longer working properly in recent versions of Thunderbird.

Some were last updated in 2010 or even earlier than that and are simply no longer compatible with the email client even if you force compatibility.

While alternatives have been created for some, there are not alternatives available for most of those extensions.

The situation is less dire when you look at Firefox which can largely be explained by it having a larger userbase and it being more prominent in general.

It is unclear why developers decide to stop working on extensions and it needs to be said that this is not a phenomenon exclusive to add-ons for Thunderbird or Firefox.

Windows software for instance gets put on hold by developers as well.

One main difference however is that the software runs fine on newer versions of the operating system while extensions may not.

From what I was able to gather, reasons for stopping development include moving over to Chrome, losing interest in developing for Firefox or Thunderbird, and being fed up with requirements to update extensions to take changes in add-on APIs into account.

If you browse the extension repository you will stumble upon extensions that are not compatible with recent versions of Firefox or Thunderbird.

That's a usability issue right there. Existing users of either product on the other hand may notice that add-ons stop to work partially or completely after updates. We have seen this several times in the past already, for instance when Mozilla switched to the Australis interface or when old APIs were replaced by new ones.

The next big wave will hit when the new multi-process architecture is enabled in the Firefox browser.

Add-ons have always been one of the strengths of Firefox and Thunderbird. Back when the programs launched, they were the only ones offering this feature (Opera had only widgets back then which worked different) and users selected Mozilla products because of it.

Some users may still use Firefox because of one or multiple add-ons that they like and use that are only available for the browser in this form. NoScript is for instance one reason why I still use Firefox and not another browser.

Mozilla faces two issues currently

  1. Add-on repositories that need to be updated. It does not make sense to display add-ons in store that are not compatible with recent versions of the browser. I'm not suggesting to remove them completely, but maybe to hide them behind a flag so that they can be accessed if users want to take a look at them.
  2. Add-on compatibility in general. It is a usability issue if add-ons stop working because of changes made to Firefox or Thunderbird. It does not really matter for users why those changes were made and if they were necessary or not. What users see is that one of their extensions stopped working as a result of it.

While 1) is relatively easy to accomplish, 2) is not. One option that may be available in some cases is to leave old code in for backwards compatibility.

Now You: Have you encountered add-ons in the past that stopped working?

Mozilla needs to improve support for add-ons
Article Name
Mozilla needs to improve support for add-ons
Why Mozilla needs to address certain extension and add-on related issues in Firefox and Thunderbird.

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  1. PhoneyVIrus said on January 9, 2015 at 4:20 am

    I’ve removed about four add-ons updating to version 34, has of now am done with extensions and will only be using the ones that I have been custom to for years. Adblock Plus, Xmarks, WOT and Menu Wizard. Even a simple one like Martin review, Open Tab Silently wouldn’t work after updating to v34, I’m only opening a link really, add-on functioning but not working. R.I.P Firefox Add-ons, I’m not updating Firefox only to remove and forget them completely. This is one of the reasons why I turn off automatic updates in Mozilla Firefox.

    Thanks for the Article Martin

  2. greg said on January 7, 2015 at 12:17 pm

    People-just stay with ESR versions if you care for addons working longer..
    Could jojo or someone else share with us names of “20+ other recently-added inbuilt and preconfigured VULNERABILITY VECTORS” so we could fix them in about :config or in other way if possible ?
    @pants could you share how to make “a small code change extension list dumper ” work .
    I assume it is not only install.rdf change.I have it installed but don’t see any button for it anywhere.Same with others installed but not working -for instance any anchor addon.

    1. Samuel said on January 7, 2015 at 5:41 pm

      What greg said, will someone please list the “vulnerability vectors” in Firefox!

      I still have Firefox installed, but I mostly use the Pale Moon off-shoot (because it’s 64-bit and allows all the add-ons I regularly use to continue working after updates).

      1. orschiro said on January 7, 2015 at 7:28 pm

        > I still have Firefox installed, but I mostly use the Pale Moon off-shoot (because it’s 64-bit and allows all the add-ons I regularly use to continue working after updates).

        Can I use the regular Firefox add-ons with Pale Moon or does it require specially adapted add-ons?

      2. Martin Brinkmann said on January 7, 2015 at 8:49 pm

        Most add-ons work.

  3. Neal said on January 6, 2015 at 3:08 pm

    I don’t have as many addons as many who visit this site(16 max at any given time), but I do see a lot of breakage. The two I am sweating over right now is autopager (broken in Firefox 36, e10), and click to play per element (broken in e10, developers asking for help to make it compatible) and Downloader(broken in e10).

    Compared to Chrome where there seem to be absolutely no breakage at all through all the years I have used it.

    If you read the documentation about Mozilla addons api, it allows almost unrestricted access to Firefox core, so when Mozilla tweaks something, it will break extensions. They are so ingrained, that you can’t turn them off without restarting the browser.

    Looking at the bug reports, sometimes the breakage is a result of very little code change, it is frustrating for users when that happens. That was part of the reason why Firefox introduced the more limited jetpack api restartless addons ( which have less breakage than traditional addons).

    Chrome extension api seems to be better designed, thought access levels. Chrome engineers can rapidly improve the core code, while experiencing very little extension breakage.

      1. wOxxOm said on February 11, 2015 at 12:32 pm

        AutoPager Fixed for Firefox 36 is now here:

    1. Denton the bear said on January 7, 2015 at 8:35 pm

      Chrome extension api seems to be better designed, thought access levels. Chrome engineers can rapidly improve the core code, while experiencing very little extension breakage.

      Google has the advantages of being slightly later to the game than Mozilla as well as having a lot more money and other resources to throw at a project. Plus Google chose to go with WebKit to underpin their browser, which again has been developed by a group of companies with far more money and resources.

      At the end of the day no product is perfect, you pays your money and you takes your choice. If you want Mozilla to be proactive join their forums and make polite and productive suggestions, not begin flame wars (if that expression is still a thing?). If you want Mozilla to be able to adapt faster then donate to their coffers, and do it on a regular basis even if that is only once a year.

      For my usage Firefox & Thunderbird are my programmes of choice, long may they both continue to evolve.

    2. Tom Hawack said on January 6, 2015 at 3:27 pm

      Firefox 36?! That’s to come, it a nightly build at this time. I think we can be happy when developers get their add-ons updated for the final release, before that is demanding a lot!

      Taking this opportunity to share a word concerning us, the users. I’m stunned when I read on AMO users complaining (even badly rating!) because an add-on is not (yet) compatible with nightly builds. That’s asking the developer to anticipate 12 weeks beyond the release. Carpe Diem, pity!

      1. Neal said on January 6, 2015 at 9:25 pm

        Firefox 37 is nighlty, 36 for beta is coming in about a week b/c Firefox 35 is released to the stable channel next week.

        All those addons I listed, it does not look very good. Autopager has been around since 2007, and the maintainer seem to have disappeared. Click to play per element maintainer mentions that he doesn’t know how to make it compatible to e10 and the AMO people offering no help whatever.

        The point I was trying to make is, all these addons, formally working perfectly will be broken by what Mozilla is doing. Some of the addons, maintainer will simply abandon b/c e10 overhaul is a lot of work. Others become abandoned, b/c Mozilla continually “tweaks” things.

        It is a serious problem, like the author said, he has experienced more than 50 percent attrition rate and it takes only that one discontinued addon that a person absolutely depends on to sour the whole experience. This will worsen, b/c the Mozilla addon api is too unrestricted and b/c of the developer flight to chrome.

        On a personal note, I begun to migrant to Chrome a bit. I still prefer Firefox, but every extension in Chrome I had since 2010 still works even if they haven’t had a update in years. Firefox on the other hand is playing the addon roulette, you are at the mercy of Mozilla engineers and add on developer’s passion. If you don’t get a luckly roll from both, it is 100 inevitable that the addon you rely on will stop working at some point.

  4. orschiro said on January 6, 2015 at 10:18 am

    I think that for Thunderbird it has partly to do with the announcement of Mozilla to only **maintain** the Thunderbird codebase but not add any major new feature to it. In other words, this basically means that the future of Thunderbird will not keep up with the future of email service development.

  5. pschroeter said on January 6, 2015 at 5:19 am

    I literally dread version upgrades for Firefox. All they do anymore is break extensions I have used for years or make bewildering interface changes I have to fight. If I wanted to use Chrome as my browser, I would use it.

  6. ElGoopo said on January 6, 2015 at 3:57 am

    Wow. People here seem to think Mozilla has infinite resources or something. I guess when an addon you use breaks, you feel Mozilla should have been perfect long ago, but all I see here is more signs that an addon used an internal API, which finally changed, but no one cared to update the addon – they just whined about it. When Apple’s internal APIs change and break software using them, is it Apple’s fault? Ditto Microsoft or Google? Of course not. Only Mozilla has the privilege of having ridiculous expectations foisted on them, by people who use free software and only donate empty negativity back to the cause. Thank goodness at least SOME people still donate.

    1. David said on January 12, 2015 at 11:58 pm

      It wasn’t well said. All the programs I used on Windows 2000 still work today on Windows 8.1. At launch some of them didn’t, but Microsoft fixed it and now everything works great. How do you think you have a point?

      Mozilla is short on volunteers because of their attitude to people who tried.

    2. Denton the bear said on January 7, 2015 at 7:32 pm

      Well said.

  7. Aminifu said on January 5, 2015 at 9:58 pm

    This may be a problem without a solution for all software developers, not just Mozilla.

    Updates (for the main app and add-ons) are necessary. They fall into 2 general groups. Those that fix bugs in current features and/or add new features (that will need bug fixes sooner or later). Then there are those that fix security issues and/or add security enhancements (with their own share of bugs or weaknesses that are eventually exploited).

    With the demand for ‘free’ apps and the backlash against ‘backdoor’ efforts to generate revenue, developers are put between a rock and a hard place. It is not realistic to expect small developer groups (or individuals) to maintain their work indefinitely at their own expense. Maybe some form of revenue sharing between the main app and independent add-on developers will help. However, even those that receive some remuneration will eventually tire of the project and move on (it’s just human nature). It also doesn’t help that many users will rather switch apps than remain loyal to what they once ‘liked’ (although some developers make it very hard to remain loyal).

    You can either stick your head in the sand and never update or just deal with the hassles of trying to stay current and secure. I chose to be current and secure (and donate to those whose work I use). It is taking longer to find current add-ons or replacement add-ons for the main apps I use, but so far I’ve been successful (or very lucky).

    1. jojo said on January 6, 2015 at 12:17 am

      Updates make you more “secure”? You’re biting on that sales pitch?
      With each update, consistently across the past 18mos, mozilla has “dumbed down” the UI, has removed preferences which were previously available, has added spyware (healthReporting)… TLS-wrapped websocket comms containing content that you, I, extension developers, have no way to inspect, that makes you more “secure”?!? Howabout SPDY, where your browser doesn’t just statelessly request assets from a server? Howabout the “browser.send_pings” and “netowrk.beacon.enabled” preferences? What the $%&#! have the clueless mozilla employees been smoking?!? (or, why the %&!#$ have they “sold us out”?)

      To the contrary (of making you more “secure”) consider the preconfigured “network.experiments.enabled=true” pref, and the 20+ other recently-added inbuilt and preconfigured VULNERABILITY VECTORS (“here, just UNcheck this tickbox and no one can activate your webcam via webrtc, we promise”). Yeah, more secure; baloney! Firebox was (past tense) a fine web browser back in the day. Nowadays, it’s a friggin “suite”, chock full of unwanted “features”.

      1. Denton the bear said on January 7, 2015 at 8:10 pm

        You sight “browser.send_pings” in your post and make it sound like something new when it has actually been around since FF v3. Also in my about:config (Linux install, FF & TB) it is disabled and this appears to be its default state. What about in your installation?

        “netowrk.beacon.enabled” (sic) appears to have become “beacon.enabled” and yes it is enabled (again Linux install, FF & TB). Yes it would be nice that when you set your privacy tracking to “Tell sites that I do not want to be tracked” that “beacon.enabled” gets set to false.

        “network.experiments.enabled” appears on my system as “network.allow-experiments” and is enabled by default. Out of interest do you know what this actually does?

        As others have asked would you please list the vulnerability vectors so that readers of this thread can read up on them and make an assessment for themselves.

        It should be taken in to consideration that over time technologies evolve, some within Mozilla’s control others not. I am sure that some users who complain about changes in Firefox and Thunderbird would complain just as hard if Mozilla never changed and stagnated, making no effort to keep up with technological changes or its competitors.

  8. Denton the bear said on January 5, 2015 at 7:31 pm

    My opinion is that if you like an addon at the very least you should praise its developer via a review, let them know you appreciate their work. Do this the minute you find an add-on important to you, no point whining about it disappearing if the developer does not know how important it is to you.

    If you really really like an add-on and the developer accepts donations make one and encourage others who use the extension to do the same.

    Many developers initially produce add-ons for the gratification of adding functionality for their own needs. While the above actions may not guarantee continued development of an add-on rewarding people in some way for their time may encourage them to do so.

    For those add-ons with a bug do not rush off and post a bad review straight away, try and engage with its developer first to see if they are working on a fix, they may not even know about it. Recently I contacted the developer of Subject Manager about a bug, providing details of OS, version numbers etc. The result was a two way conversation ending with a new release being sent out within a short period of time. Yes I have practiced a little of what I have preached by making a donation as a way of expressing my thanks for the update.

    Now I am off to make my annual donation to Mozilla to thank and reward them for their continued development of their software.

    1. Pierre said on January 5, 2015 at 7:49 pm

      I had made a donation to Contacts sidebar. However he abandoned his extension

  9. Jim Ranson said on January 5, 2015 at 5:46 pm

    One good example is ForecastFox a nice weather app that pulls its data from Accuweather. With the recent spate of updates to Firefox the ability to access and change information on the extension’s settings page is dead. There is a work around to get the extension working in current version of Firefox. It is a PIA if one has to setup a new install and have to copy files from one computer to another in order to get the extension to work. You still are unable to change any of the extension’s settings.

    Another example is ReadItLater aka Pocket. They currently have an extension which still appears to work but will no longer be updating and instead want people to use their new Add-On Service for Firefox. The problem is with the Add-On Service is that Pocket has absolutely no information on their website regarding this Add-On Service if you have problems with it I spent countless hours trying to figure out why the Service would not work on Firefox. It was because NoScript was not whitelisting a site that the Add-On Service requires access to. I can not remember the last time I had this type of problem with NoScript and an extension since I can usually tell via NoScript if a particular site is blocked. With Mozilla’s Add-On Service NoScript shows nothing being blocked.

  10. Claude LaFreniere said on January 5, 2015 at 5:05 pm

    There’s also the case of the dispapereance from Mozilla web site of add-ons such as “Redirect Cleaner v. 3.0.0” with no explanation…

    1. jojo said on January 5, 2015 at 11:58 pm

      Yes, I noticed its disappearance and tried to track down a copy on github or elsewhere, with no success. The blog article I had read which recommended it was posted only a few months ago, so the disappearance must happened recently, I guess.

      1. Blue said on January 6, 2015 at 8:04 pm
  11. unyk said on January 5, 2015 at 5:02 pm

    With it’s market share now under 12% worldwide, it wont long before it enters single digit & we can finally say goodbye to this menace. So long Firefox, it was nice knowing you.

    1. Tom Hawack said on January 5, 2015 at 5:33 pm

      In what is Firefox a menace?

      I’ve always used Firefox ever since its 2.x version and most of the time as my default browser. I like it, I like what I perceive of the Mozilla philosophy. I’m a bit disapointed (to put it mildly) with the curve the company initiated starting with Australis.

      The Web is what it is, a jungle, and more Firefox will decline in terms of market share more it will be attacked as a menace, a piece of craps, a nonsense etc. etc..

      One can criticize and remain objective, or at least try to avoid mass hysteria.

  12. Ahmad said on January 5, 2015 at 3:20 pm

    Title needs to be “Mozilla needs to improve support for add-ons” rather than “Mozilla needs to do improve support for add-ons” IMO.

    1. Pierre said on January 5, 2015 at 3:48 pm

      Very important correction…

    2. Martin Brinkmann said on January 5, 2015 at 3:38 pm

      You are right, not sure how this got in there. Corrected. Thanks!

  13. Pierre said on January 5, 2015 at 2:25 pm

    That’s right for Thunderbird
    Many extensions developers have no longer wanted to maintain them, sometimes for many years. Impossible to force them…
    ex : contacts sidebar, feature which should be built-in in TB
    in spite of it it’s still a part of “featured extensions” : “inadmissible”, as German say !

    Thunderbird is not so used as Firefox and the effort is not worth it, and is a heavy and complicated program

  14. Tom Hawack said on January 5, 2015 at 1:16 pm

    This article points out what many, many, many users either shout, whisper or simply silently think, exasperated.
    Here I’ll write it, as well!

    Concerning Thunderbird, very few add-ons and no add-on compatibility issue since the very few I have have (very) luckily been updated.

    Concerning Firefox, the leaders of the band seem for most of them to have developers making the effort, considerable some times, to update their add-ons accordingly to Mozilla’s latest phantasms — forget that word — brilliant projects for a post-modern browser, toaster soon included if it goes on this way.

    I have encountered several add-ons, worthy, valuable, sometimes most valuable IMO which have been simply abandonned by their developers, fed up (some developers did not hesitate to use that expression) by Mozilla’s hysteria to come up with extravagances which may appear more in touch with the quests of a few high-profile techies than with that of everyday users, unless the policy is to take into consideration the only new everyday users, throwing to their faces what these techies consider as the sum-mum of a browser’s technology…

    The next big wave will hit when the new multi-process architecture is enabled in the Firefox browser.“. Indeed, Are we e10s yet? ( shows the effort of developers to respond once again to Mozilla’s mutations and promises its lot of add-ons to be abandoned.

    Are all Mozilla’s seeks worth it? Not sure.
    The Callig and Conversation feature (Hello? Anybody Home?), worth it?
    The New Render features currently responsible for “hanging tabs” on some systems, worth it?
    The New Search UI, unfinished, worth it?
    The Network predictor (OFF by default at this time), worth it?

    Mozilla indeed is wrecking 10 years of its identity, it started with Australis and its continuing its blind quest to the summits which may very well appear as a one-way ticket for the cemetery. I’m afraid it is the company’s very policy which is on the wrong track.

    1. ElGoopo said on January 6, 2015 at 4:05 am

      I guess it’s easy to get on your pulpit and focus on a few of the bad things that happen, while ignoring the good. Hell, I’m sure the response to this will be “what good have they done?”, because the people who make these kinds of arguments don’t CARE about the good stuff, they just want to bitch about the bad stuff and wag their fingers. Being constructive or even fair is not the name of the game. Addons break, but it’s not because they were old and relied on internal APIs prone to change, but because “Mozilla is bad and should feel bad because I say so”. After all, why bother trying to fix the addons? That takes effort! Far easier to just blame everything on Mozilla.

    2. clas said on January 5, 2015 at 2:49 pm

      i agree. mozilla is catering to the very few. but i watch and laugh at the constant new updates. happily contented with an older version where everything just works. safe and secure behind security measures set up over time…never a virus or attack or freeze up in 11,000 hours of daily use.

      1. ElGoopo said on January 6, 2015 at 4:09 am

        @tuna. Pale Moon *is* Gecko. In fact it’s just a rebranded Firefox with some slight tweaks. What a bloated piece of “shark jumping” junk, amirite? It’s also perfectly fine for Pale Moon to break addon compatibility like they did in the last version, but when Firefox does it? They’re horrible.

        Firefox even has an addon subsystem that doesn’t require updates every 4-6 weeks. But do people care about reality? No. Their old addons broke, and they just want a placebo to make them feel better because they don’t contribute anything to the effort except a lot of hot air.

      2. tuna said on January 5, 2015 at 5:47 pm

        I third this sentiment! Change for the sake of change serves only the changer. Add-on developers should NOT be required to tweak their product every 4 or 6 weeks b/c Moz feels the need to participate(create) a features race. Seems more of a “shark jumping” competition, IMO, as the bloat and potential future exploits keep getting packed in under the hood.

        Cue up my broken record: for those who prefer the gecko model and do not crave all that is new & shiny, there is, thankfully, Pale Moon & Waterfox.

        Viva bifurcaciónes!

  15. Daniel said on January 5, 2015 at 12:55 pm

    Yup, i just don’t know how the devs (and end users) are going to make it through the “next big wave” you talk about Martin.

    Take Diigo for example.
    The Firefox extension works just great (compliments to the cie. for maintenance) but it is a different extension when you get it for Google Chrome!

    The way i see it, we’re heading for either separate desktop apps (like Evernote for Windows) or everything integrated in the cloud like Google. Personally, i like to have things on the desktop (Bing desktop search has been an excellent invention on behalf of Microsoft!) but then again, i also like to have things in the cloud like Dropbox. It’s a dilemma… and like David said, if Mozilla keeps up with it’s lazy attitude at up-keeping its add-ons, my hunch is, they’re going to loose devs + end users even more, perhaps to the point of no-return. But Lord knows how i hate monolithic structures that monopolize you! Part of our present world situation too huh?!

  16. Pants said on January 5, 2015 at 12:48 pm

    I have 80 or so extensions – nothing has broken over the last 3 years or so except a couple needed a small code change (extension list dumper was one from memory) or I found a fork

    BUT .. and i am dreading this …. I’m on the beta cycle (and run a portable Firefox which I backup prior to manually updating) .. when I updated to 35 a few weeks ago .. almost every extension broke. I rolled back to 34, updated again .. same thing. I’m guessing ONE of my extensions is causing the grief but will wait until 35 stable rolls out.

  17. David said on January 5, 2015 at 11:44 am

    The thing is, Mozilla should have nailed this by now. There’s only so many times you can ask your developers to re-do things because you failed to properly future-proof your API. People are tired of updating their extensions due to Mozilla’s laziness.

    Some of the API changes are purely name changes. Compatibility with these could be automatic. It isn’t and this reveals Mozilla’s position on the topic: they don’t care about extensions.

    Mozilla should also only add closed-code features as bundled extensions, rather than polluting the main code. That might help them focus on the right things.

    1. ElGoopo said on January 6, 2015 at 4:16 am

      Future proof it? How? If an addon uses an internal API, and that API eventually changes, it’s up to the addon to fix itself, not Firefox. If it’s a public-facing API, sure, but then people should really be using the APIs that don’t break as much, and request for Mozilla to make public and stable versions of the APIs that aren’t meant to be public-facing. The addons that use the more modern addon format simply don’t break on their own often, let alone every 4-6 weeks. Ones that MUST use more advanced APIs because they do really complicated things will of course break more often. But that’s the same no matter where you go. You either commit to what you wrote, and properly maintain it, or you eventually run into problems. Mozilla can only do so much. They can’t be faulted if people abandon their addons because they chose the wrong APIs to work with, or it’s just too difficult to maintain them and no one else wants to. Besides, if Mozilla kept endless versions of their APIs bundled with Firefox, you’d only complain about how slow and bloated and convoluted it is. They can’t win either way.

      1. David said on January 12, 2015 at 11:39 pm

        Have you thought about applying to Mozilla for a job? I think you’d fit right in with your attitude.

  18. Seban said on January 5, 2015 at 11:23 am

    I remember Dictionary Switcher (FF & TB) not working for a while after Mozilla changed something on the implementation of dictionaries. Then there was HTTPS Finder (FF) which still exists but not on the Mozilla websites. I don’t know why the developer decided to remove it.

    Luckily apart from that all the add-ons I use worked fine most of the time and still do.

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