It’s almost 2026 and I’m switching to Thunderbird for email. After 20 years of cloud services and now the era of AI, it took some adaptation.

Why am I switching to Thunderbird?

  • I don’t want to encourage GAFAM services, such as Google or Microsoft. Too big, too unethical, unregulated and US-based, where the current political climate is too unstable and incompatible with my values. We are their product, not their clients.
  • I don’t want to use AI for email. I use AI for other things, but I don’t want it in my email. AI is good for learning, but it makes us lazy in day-to-day things. Email is very personal and sensitive. I don’t want AI in my email.
  • Thunderbird has been around forever, like Firefox, and even if we should not take it for granted, it’s a fairly solid base. Most open source projects backed by a single company tend to pivot and disappear.
  • Thunderbird exists on all major desktop platforms (including Linux) and Android, and eventually Apple iOS (maybe in 2026?).

Admittedly, I never really used neither Gmail or Outlook. I use my own domain name and I always hosted my own email server. You probably don’t want to host your own email server, but you can more easily adopt Thunderbird. It’s a first steps towards getting rid of GAFAM.

That said, Thunderbird is OK out of the box, but required tuning for me. If you have more than one email address (personal, work, etc), here are a few tips I found useful:

Open in new tab

I have 3 primary email addresses (2 jobs, 1 personal), and was finding difficult to keep track of all 3. I wanted to keep my work out of my personal inbox, so “unified layouts” are not useful to me.

What I found most useful was to right-click an inbox (on the left pane that lists all accounts and olders), and then “open in new tab”. This way I have a tab for each email account. I cycle between them by using the keyboard shortcut “alt-1”, “alt-2” and so on.

Number of replies column

The threads in Thunderbird took me a lot of time to get used to. I would not see that I had new replies in some conversations. I didn’t like the “card view” because it was not compact enough.

The most helpful indicator I found, was enabling the column “Unread”. Right-click on the list of columns, and enable it. It displays an indicator with the number of unread messages for a given thread. There is another indicator “read indicator” (statut de lecture) which is only a green icon, and that’s too subtle and not as much information.

Screenshot the Thunderbird inbox

Quick Move extension

I try to avoid Thunderbird extensions because they tend to break after upgrades. However, I found Quick Move to be reliable and absolutely essential.

Everyone tells me I should use more server-side filters, but I receive a lot of email from a lot of people for various topics. Filters often don’t work for me. And I want to be able to archive those emails in a way that I can find them later on (because the search isn’t terribly good).

By using the Quick Move extension, after reading an email, I type “Ctrl+Shift+N” and then type a folder name, which gets auto-completed. It also displays a button in the toolbar, in case you forget the keyboard shortcuts.

Another reason why I use folders: search isn’t terribly good on desktop, but it’s even worst on mobile. It’s not particularly smart, and it only searches local messages that have been downloaded on the phone. At least this way, if I’m looking for an email on a specific topic, I can open the folder and search within that folder.

Speaking of search on mobile, by default Thunderbird will fetch something like 50 emails. It will load more if you scroll. So if you’re looking for an old email, you will have to scroll a lot, then search.

To fix this, on Thunderbird of your mobile device, go to the Settings, then select an account, then go to “Fetching mail” (something like that), and then “size of the local folder”. Select something like 1000 emails. Unless you receive a ton of PDF documents by email, it should not have a big impact on your phone storage.

Date format

I use Thunderbird in French and English. I could add spelling dictionaries for each language, and change the interface to French. However, date formats annoyed me, it was either M-D-Y or D-M-Y. I want Y-M-D, which is usually widely understood in Canada (and is the standard format for government forms).

Go to Menu > General > Configuration Editor (button), then enter intl.date_time.pattern_override.date_short in the search box, select “string”, and enter: yyyy-MM-dd.

Once set, the date format should work for parts of both email and calendars. I’m still confused and trying to figure this out.

More information on support.mozilla.org.