You may now install uBlock Origin in Thunderbird

Martin Brinkmann
Apr 29, 2023

Thunderbird users may install add-ons for the email client to add new features and other improvements to the application. The selection of available add-ons is large and includes add-ons to archive old emails automatically, verify DKIM signatures, sort mail folders manually, or add Send Later functionality to the email program.

Now, Thunderbird users may also install the popular content blocker uBlock Origin directly. The change was revealed yesterday on the official GitHub repository of the project.

Thunderbird users may select Tools > Add-ons and Themes in the application to open the Add-ons Manager. There, they may select Add-ons, if not selected already, and use the search to find uBlock Origin.

The extension has no users currently as it is brand new. A click on it and then another on the install option starts the installation process. It should be listed under add-ons afterwards.

Thunderbird users find the uBlock Origin button in the mail toolbar afterwards. It is not active all the time, but that is understandable, considering that an email program works differently than browsers.

Emails are not touched right now by the content blocker. The maker of uBlock Origin, Gorhill, explained this here. According to Gorhill, uBlock Origin does not have access to emails at this stage and that it may be used to process feeds displayed in the email client currently only.

Thunderbird may be used to display RSS feeds in the client. It is not the best RSS Feed reader, but it may work for users who subscribe to a small number of feeds. These feeds are downloaded when accessed and they may contain elements that users may not want to see.

To view RSS feeds, Thunderbird users need to create a Feed account in the Account Manager. This account is then listed in the sidebar, and feeds may either be imported from another supported program, or added manually.

Most Thunderbird users, every user who does not read feeds in the email client, may not need to install the current version of uBlock Origin. This may change in the future, especially if functionality such as tracker blocking could be implemented for emails.

You may now install uBlock Origin in Thunderbird
Article Name
You may now install uBlock Origin in Thunderbird
The content blocker uBlock Origin has been released for the Thunderbird email client. We take a first look at what it does and what it does not do.
Ghacks Technology News

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  1. Anonymous said on May 1, 2023 at 11:25 pm

    What’s strange is that I remember trying to install uBO with success many years ago in Thunderbird, to filter email contents, before resorting to never bypassing the default that blocks all remote content (by the way it’s not a binary choice, the default can be overriden for specific emails, making uBO even more relevant).

    Maybe this has to do with Thunderbird radically limiting extension capabilities following with a delay the old Firefox Quantum transition to webextensions. Maybe uBO had to start anew there.

    Theoretically even with no remote content uBO could have some use for cosmetic filtering also, in addition to URL cleaning that was already mentioned, but I never found that necessary in practice. However I receive very few trash mail to be cleaned anyway.

  2. gazoo said on April 30, 2023 at 6:14 pm

    Completely unrelated comment, apologies in advance.

    ghacks has undergone some major changes and and I was wondering if I should remove it from my feeds. I decided to try the following:

    BOOM! It’s like getting the old site back.

    1. gazoo said on May 3, 2023 at 5:31 am

      Oops… It does not work. I have a FF extension named “Feed Preview” by Guido Berhörster. When I access a feed page directly (xml, etc), it displays the results is a nicely formatted page.

      It did so with the link I pasted above. When I tried pasting the link into my Feed Reader… nothing was there for my reader to grab. I know some sites break up their feeds by author. I thought ghacks was doing the same and ‘Feed Preview’ led me to believe this.

      Still, it’s a good idea. I would love to have access to Classic ghacks via a direct link to Martin Brinkmann’s articles.

  3. Karen said on April 29, 2023 at 5:48 pm

    Thunderbird used to be a great email client. The interface now is not user friendly. I will not spend lots of time one one application, when there are better ones out there.

    1. Anonymous said on April 30, 2023 at 6:14 pm


  4. Mystique said on April 29, 2023 at 3:13 pm

    I don’t imagine there is a huge need to add too much to Thunderbird but the one thing that is definitely needed is to be able to clean up url’s from trackers and such which uBo could potentially do.

    It boggles my mind why Third party email clients such as mailbird and postbox cannot do this or makes no attempt to do this. It just goes to show how important things such as uBo and the filterlists are.
    Huge credit to those that create and maintain these list. You’re doing gods work. hahaha.

  5. Tom Hawack said on April 29, 2023 at 1:46 pm

    @linuxfan, OK. If I had anticipated your pertinent remarks I could have added :

    1. Redundancy. I agree and for that I backup emails with the ‘MailStore Home’ free email backup application.

    2- Convenience. Indeed. How inconvenient it is to check Webmail (moreover with login) on a regular basis, not to mention an urgent email. because of that I use an application called “Pop Peeper’ to check my email providers. Be noted that I used ‘Pop Peeper’ even with Thunderbird given the former is much liter than the latter.

    3- Security and privacy : depends of course of the email service provider. One can choose to read emails in text by default and if HTML (default or per-email) is chosen, indeed included javascript may be a concern though not any hosted to or calling upon a 3rd-party (remote content) given uBO intervenes.

    When it comes to security & privacy I believe moreover that my email, fully encrypted on a serious host such as Posteo is far more secured than it is locally with an email client.

    Provided what I could have mentioned to start with, I remain convinced that an email service provider prevails on an email client :=)

    1. Kirk said on May 2, 2023 at 6:18 am

      We get it. You use Posteo :p. Sadly, it has no free tier and most ordinary folks won’t even have heard of it.

      1. Tom Hawack said on May 2, 2023 at 12:48 pm

        @Kirk, the cost is one thing, the popularity is another.

        The cost: you know as well as i do that focusing on free of cost is far less pertinent than trying to determine if the price is worth it, globally and for ourselves (co called the “opportunity cost”). In my view 1€/month when regarding what it offers, in terms of privacy, security, features [] is worth it.

        Popularity, “Folks won’t even have heard of it.”. What do we know of what “folks” have heard of, use or not, like or not? Regarding Posteo, it has its users and is acknowledged as a serious Webmail service, even by those who don’t use it. From there on if “folks” is to be understood as blind followers who go where the fashion/trends leads them to whilst less famous application, products as reserved to an elite of sharp, technically skilled geniuses then of course your reply is deeply pertinent.

  6. Tom Hawack said on April 29, 2023 at 12:47 pm

    Be noted that accessing a Webmail provider within a browser of course running uBO has uBO functional as is.

    I’ve been a Thunderbird user for years but when I discovered all the advantages of Webmail I decided to abandon the former and manage all my emails with an email service provider (other than Google Mail, Yahoo Mail, Microsoft …) and I opted (mainly) for Posteo.

    Not only uBO does it’s job as it does with any other site but another advantage I found was that the sender’s IP is that of the email service provider. Also of course accessible from anywhere, not bothered by the requirement of an email client, no bother with an email client’s updates, bugs … personally I have enough with tweaking the browser (Firefox) to not have moreover to spend time with an email client.

    I mean : what’s the advantage of an email client over an email service provider (Webmail)?

    1. Anonymous said on May 2, 2023 at 12:16 am

      “I found was that the sender’s IP is that of the email service provider.”

      It’s not always the case with webmail providers, although they send their own IP address normally, sometimes they add an extra special header with the IP address of the user who connected to the webmail site. Such behavior with webmails and local clients is an underestimated privacy issue, basically telling to all the recipients for example what cities the emails were sent from.

      On the other side there are webmail providers such as Disroot that not only do not send the IP address of the connected user who sends an email, but also even clean the sender IP address from received emails, which is sort of unusual, protecting the privacy of email contacts “against” the user himself.

      1. Tom Hawack said on May 2, 2023 at 2:20 pm

        @Anonymous, many thanks for your comments regarding a touch of deeper inspection of POSTEO’s features, reliability and comparison with email clients. Frankly I’m not sufficiently technically oriented to bounce on each of your remarks and i’ll have to admit understanding them more or less as blurred so to say. I’ve exposed what I know of Posteo perhaps without any further enhanced analysis. You may be totally right.

        There’s always a balance to establish between what we know (or think we know), what we ignore (given we’re aware of what we ignore) and a product’s announced features. Between trying and avoiding, between blind confidence and blind distrust there’s a no-man’s land which nevertheless is the only one to consider when aiming to make the right decision, it’s called the risk and given we optimize its calculation than IMO it’s a go. But, as always, mistakes are possible and i admit that I may very well over-estimate Posteo. Which is why information such as that you provide is always worthy. Thanks.

    2. Anonymous said on May 1, 2023 at 11:18 pm

      “I mean : what’s the advantage of an email client over an email service provider (Webmail)?”

      In addition to what was already said.

      If using POP3, not needing access from different devices, and not storing checked email on the server, but that may be an uncommon use case, the benefit is not only about having a local backup, it’s also about not leaving email on a server if not needed.

      Otherwise, even is using IMAP.

      The webmail provider won’t display ads, in particular ads that are targeted on email contents. There won’t be either the other sorts of nuisance that abund on the web, beyond mere clutter.

      Related, the email provider will be pressured to comply with email standards that are not under its control. Google would really love everyone to just use Google webmail and local email clients to die, for that reason too, and is already taking control of the email protocol enforcing a web protocol of theirs for authentication even in local clients.

      “Anyone accessing your email client has all your credentials at sight”

      It is possible to set a master password in thunderbird too. And contrary to a browser’s password manager, this one won’t fill password fields on attack sites with your passwords every time there is a security bug.

      “more important are its privacy/security features I doubt any email client includes :
      A- Crypto mail storage which “encrypts your entire email data at the press of a button, including all content and metadata.””

      The provider in that case can still read all new incoming (before they encrypt them) and sent emails. Not leaving emails on a server at all is at least as good for privacy. If not an option for convenience reasons, the provider should provide local software (a thunderbird plugin, for example) for compatibility with its encryption. Some other providers, actual fully end-to-end encrypted (at least between users of the same service) email providers such as Protonmail, used to have such tools available if I remember well. Interestingly the Posteo site reminds, on that subject, that PGP encryption was available on local clients long before being possible on (a few) webmail services.

      “‘TLS-sending guarantee’ and ‘TLS-receiving guarantee’ :”

      I have looked at Posteo’s transport encryption between providers on their site and found that a bit excessive, simply not allowing email communication with providers that don’t support transport encryption, what does one do in case one really needs to send or receive that email, smoke signals ? But I’m not sure of how universal transport encryption between providers is supposed to be right now, maybe it’s their way to pressure a few bad providers and they’re strong enough to do it ? The announcement about it being almost 10 years old, I don’t know what to think about it.

      But while reading that I found another interesting issue about using DANE/TLSA to actually truly do authenticated transport encryption between providers instead of the fake, unauthenticated transport encryption that is the standard without that, and that can be intercepted by a man-in-the-middle attack, thanks to a huge and well known hole in the email encryption protocol that is well known but strangely very few in the privacy communities talk about (it’s only the second time I read someone about it, last time it was the EFF as a small side comment in 2020, But it’s also in the 10 years old announcement of Posteo, not sure what the current state is.

    3. Yash said on April 29, 2023 at 7:50 pm

      An email client allows for accessing of multiple email accounts of different providers and multiple aliases without depending on one to handle everything. Sure you can use one providers browser client and add other providers email accounts but I prefer independence. Also UI is lot more stable and generalised between different providers.

      It also declutters browser. If I want something to do with email, I use email client otherwise I’m happy in browser. Most of the time I try to do everything in browser and not install specific apps because browsers provide better privacy and security measures. But in case of email clients and select few other apps, I prefer dedicated separate app from browser.

    4. ECJ said on April 29, 2023 at 5:10 pm

      I agree that using email in a browser does have benefits. As you mentioned, things like uBlock Origin will be active, a browser will likely be more secure than a third-party email client – and the other advantages you mentioned.

      However, a local mail client has the below advantages:

      1) for example is dog slow in a browser – even more so if you have quite a few mail folders. A local email client is a lot faster.

      2) A local email client works offline, meaning all emails are still readable with no internet connection – such as when travelling.

      3) A local email client provides notifications, not only for emails as they arrive, but also for calendar events as well. Therefore, calendar event notifications will also work offline.

      4) A local email client contains login information stored separate from the browser. Therefore, when clearing browser data/cookies, it’s not necessary to log back in.

      5) Some webmail pages are too bloated and can be too overwhelming for non-techie people who just want basic email/calendar/contacts, without a bunch of other crap thrown in there.

      If the above issues were sorted, then I would likely go back to using webmail.

      1. Tom Hawack said on April 29, 2023 at 6:48 pm

        1- is understandably slower in a browser given it’s basically far more than an email client given it is built as a component of a software, it’s a webmail service part of the Microsoft 365 product family, which is software. will inevitably be slower in a browser because of that as I understand it though i’ve never used it myself.

        2- All emails, and from any/all email providers are accessible (readable) offline given they’ve been backed up with an email backup application such as ‘Mailstore Home’ which I mentioned before.

        3- If an application such as ‘Pop Peeper’ can check for new email it cannot indeed check calendar events : that’s one advantage for an email client need to say.

        4- Login information remaining available is maybe not a true advantage in terms of privacy. Anyone accessing your email client has all your credentials at sight. A user with privacy in mind should logout once he’s over with the work. Password managers make it a breeze to login. If he doesn’t log out when exiting his Webmail service then two consequences : privacy issue if cookies haven’t been cleared, so clearing them is an advantage, not a drawback IMO. Cumbersome? Not with an email checker such as ‘Pop Peeper’ …

        5- Some webmail pages too bloated? I haven’t tried them all, some might be, some might not. In my case ‘Posteo’ is 100% intuitive, spatious, I’d even say far more comfortable than Thunderbird as I remember it and perhaps far more than its latest versions are given software in general tends to bloatware …

        I’m not advertising Posteo when I note that aesthetically it now includes a highly configurable User Interface, with a variety of skins including Dark Mode … but more important are its privacy/security features I doubt any email client includes :

        A- Crypto mail storage which “encrypts your entire email data at the press of a button, including all content and metadata.”

        B- Transport encryption with two options : ‘TLS-sending guarantee’ and ‘TLS-receiving guarantee’ : always send your emails via an encrypted transport route, always receive your emails via an encrypted transport route … if sending or receiving was blocked you get informed immediately by Posteo. I call that true security.

        Sorry for being lengthy. Beyond rational arguments there are as well personal preferences of course. But besides point (3) and calendar notifications I’m not convinced of any other email client advantage!

    5. Shiva said on April 29, 2023 at 1:37 pm

      > I mean : what’s the advantage of an email client over an email service provider (Webmail)?

      In addition to those already mentioned, I must say that I have only recently started to look into and use a few add-ons on Thunderbird and a couple of them make your life easier (CardBook, ThunderHTMLedit, QuickText).

      I still do well managing accounts with an e-mail client with POP3 protocol and backup of relevant communications. I suppose it also depends on business needs.
      As a general mail account I just signed up for Infomaniak’s free offer (limited to some countries), I have yet to take a look at Posteo or Mailbox.

      But if you are so comfortable with a webmail service, have you evaluated Tutanota? It does not support IMAP\POP3 but as a start it is free.

      1. Tom Hawack said on April 29, 2023 at 1:53 pm

        @Shiva, I had tried Tutanota but the problem was that its management of alias email addresses was a true pain given those chosen by the user could be removed but remained counted and could not be replaced …

        Posteo is far more flexible :

        “You can set up two aliases here, free of charge. From the third alias onwards, a cost of 0.10 EUR per alias per month applies. You can add as many as 20 email aliases.”

        This is a true plus, for me who uses aliases as well as anonymous email (AnonAddy here), and the former rather than the latter for confidential exchanges.

    6. linuxfan said on April 29, 2023 at 1:01 pm

      > I mean : what’s the advantage of an email client over an email service provider (Webmail)?

      1. Redundancy: If your email provider terminates its service (for whatever reason) you still have your mails on your disk if you fetch them via POP3.
      2. Convenience: If you keep your email client running you’re immediately informed about new mails without the need to stay logged in with your webmail in an extra browser tab.
      3. Possibly security and privacy: Javascript is disabled (and cannot be re-enabled) for mails in Thunderbird, and any remote content is blocked by default. This is not necessarily true for your webmail – although Posteo is a good choice.

  7. ECJ said on April 29, 2023 at 12:00 pm

    “…This may change in the future, especially if functionality such as tracker blocking could be implemented for emails.”

    Yeah. To me the main purpose for adding a content blocker to an email client would be to block email trackers/beacons. Similar to what eM Client does in their paid version:

  8. fred said on April 29, 2023 at 7:01 am

    This is not new news. I remember installing ublock on thunderbird last year.
    what is the difference

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