Google Calendar in Thunderbird tabs

If you’re a Google Calendar user like myself you might want to check out this really simple add-on for Thunderbird, which should be available as an official add-on for the coming Thunderbird 3 release.

The Google Calendar Tab

As simple as it sounds, this adds the Google Calendar web interface as a new tab directly into Thunderbird.  Creating and viewing events works just as it would in a browser like Firefox. 🙂

Google Calendar Tab

If your calendar is setup to show popup alerts you’ll continue to see them from the calendar tab while in other, mail, tabs.

Here’s my family Pinochle game reminder alert showing.

Google Calendar Alerts

There is no official release of this extension yet, however you could grab the latest XPI, download and install it into the latest (at least rc1) Shredder release.

More Extensions

It’s easy to get started integrating a web application like Twitter, Remember the Milk, and other sites into Thunderbird.  Once you get the initial pieces you can start working on better integration into your email conversations.

If you’re interested in creating an extension similar to this one, here are a couple links you probably want to check out:


This calendar extension only handles a single url for Google Calendar.  If you’re looking for actual calendar integration with different calendars, including google calendar, you’ll want to check out the Lightning Calendar extension which also runs inside Thunderbird tabs.


248 thoughts on “Google Calendar in Thunderbird tabs

  1. You know? The Thunderbird developers are really starting to tick me off. Yes I understand they are trying to put a nice product out there, and it’s a free p0roduct and all of that. But one of the main reasons it’s so powerful and desirable is the add-ons!!! And so whenever they make a change, half of my add-ons are disabled.
    I wonder if there is a possibility of some kind of co-operative effort between them and the add-on developers to share information so add-ons could be ready to go on or near the change date. Even my AV hooks are disabled in ver 7 of Tbird. Yikes.
    OK, now I’m finished whining for a while and I’ll go back to being a happy (mostly) user of Tbird.

  2. I kind of agree but doubt that would ever happen (have similar issues with WordPress plugins sometimes). I got the notice for the Thunderbird update and usually just “do it” but I need my calendar up because I log into too many google accounts for my clients so a browser login doesn’t work. I decided to NOT upgrade right now because I don’t have the time to deal with an add-on like my calendar not working.

  3. Fully agree on all comments: the best and most useful add on I never had.
    I promise not to upgrade Thunderbird anymore to keep your add on alive 🙂
    Great job…and I need your halp to make it work again :-)))

  4. One of my fave add-ons as well and have no intention of upgrading my version of TB until it’s compatible. One of the “hidden” features I discovered accidentally was that I can use Calendar Tab to load my Google Reader into a TB tab as well. That way, every morning I can get my email, schedule, and latest reader updates all at once, all in one interface. Brilliant.

  5. It DOES work with TB 7 if you change the version nr. to 7.*.* in the install.rdf.
    It’s a brilliant solution: No need for lightning anymore, just open your Google calendar and work directly in the cloud!
    There should be a task function though…..

  6. @BarnOwl – would you be willing to give more detailed instructions to a clueless person? Where do you find the install.rdf?

  7. Ok, you’ve got the google_calendar_tab-3.8-tb.xpi. Now, go with an archiver in the archive, I use (search it on Google, it’s free)
    There you will find the install.rdf. Open it with notepad and change the version nr. to 7.*.*
    It should work to TB 8 now!

  8. Dear BarnOwl and April – tips for anyone even more clueless?? I have a windows 7 OS so no idea where the file is or how to go into the archive..? I just have an updated Thunderbird telling me Google is disabled?

  9. Sorry but I guess I am not conversant enough to follow it….

    Where do I have the xpi? How do you use (archiver?) to “go” in the archive (where is the archive?)

    Sorry, I saw your post above, but it is not *quite* explicit enough for me to follow it – my failing yes but hoping you could give just a little more of a pointer 🙂

  10. The xpi (google cal tab) is just a few files that make up the program. You’ll find it where you put your downloaded extention.
    If you have 7-zip you go to the calendar tab file (xpi) and open it.
    There you will see a few files, now open install.xpi with 7-zip and alter the version file.

    I’m sorry, but I cannot put it any clearer here……good luck!

  11. @BryanClark

    THX FOR MAKING SUCH A GREAT ADD-ON (Hope Mozilla is putting you high on the pay-list)


    THX for your explanation. I did all of that and it seems to be working.

    To me you will all be kind of magicians

    All the Best

  12. For those that are having problems with the new Thunderbird Version,

    1) Get –
    2) Open the google_calendar_tab-3.8-tb.xpi file in
    3) Edit the Install.rdf
    4) Change the Version #, like so (2 places, Version and MaxVersion):

    Google Calendar Tab
    Bryan Clark


  13. I love the Google Calendar plug-in. Thank you for developing it! The only problem I’m having with it is that the task pane is empty — I can’t see existing tasks or add new ones. Everything works fine when I bring up the calendar in firefox. I am using Thunderbird 8. Does anyone else have this problem? Any suggestions for working around it? Thanks.

  14. I just found a way to get Google tasks in a dedicated Thunderbird Tab. To do this, I hijacked the GoogleMailTab XPI file ( I modified the googlemailtab.js file inside of the jar file the to point to instead of Then I installed the XPI file in Thunderbird. When I click on the gmail icon, I get a tab where I can view and gmail tasks.

    I tried using the canvas URL (, but that had the same empty task list problem as discussed above. It’s probably a problem with how the embedded Thunderbird browser handles javascript. The android version of the page doesn’t use the same javascript code, so it doesn’t cause that problem. I also tried the mobile version of the page,, but I prefer the android version.

    Bryan, would you be willing to create and post a new “Google Tasks” extension using this approach? I’m sure you’d make quite a few people happy!

  15. Is there any way to make Google Tasks appear in the Tasks section on the right hand side just as they do when the calendar is viewed in a browser?

    Many thanks for the excellent add-on – Joe

  16. There seems to be a problem updating google calendar tab to version 9.0.1. Before, the fix with the install.rdf file always worked great. I was able to update to version 7 and 8. But now when I change the version numbers to 9.0.1 google calendar tab won’t open anymore. Any suggestions? This add-on is great and I don’t want to miss it!!!

  17. hi there,
    is there a way to change a saved user/password combination inside the g-cal-tab in tb?
    saved it once and have to change it now – couldn’t find a way.
    VERY thankful for your attn/help.
    yours, roland

  18. I always get “slow connection you just for reading” 🙁 when I trs to get google calendar via Google Calendar tab. There is no problem at all when opening google calendat via Firefox. xpsp3, ff10, tb10.

  19. Is there any plans to bring the task functionality of the google calendars into the google calendar tab? Currently the task list doesn’t load in the tab like it does in the browser.

    Other than that, great plugin!

  20. I generally really like the plugin, but I often have problems with it not syncing any longer. The solution seems to be to kill the plugin (click on the X and close the tab) and then click on the calendar icon to reopen and re-login. That seems to fix the problem for a time, at least. Irritating, but not a killer! I suspect trying to debug this will be very difficult.

  21. Hello,

    I’m using Google Calendar Apps with Thunderbird 10.0.2
    When i’m using the options of one of my calendar, links (“Share calendar”)with javascript seems not working.
    The javascript is enabled in TB config.

    Any ideas ?


  22. It would be SWEET if you could integrate to the point that I could choose to have a .ics attachment on an email imported into a specific calendar in my Google calendar. THAT would be awesome.

  23. I have the tasks pane on teh right hand side of my calendar but I can’t get any tasks to display. Can you help please? Thank you

  24. Hi,

    I’ve been using the Google Calendar Tab for more than a year now and it works perfectly! What a simple and neat solution!

    However I’ve got one question. I’v recently been getting quite a lot of outlook meeting invitations. Is there a way to add those to my google calendars using the Google Calendar Tab from within TB? I know that the usual way would be to use add -> import , etc. but I don’t see this option from within TB.



  25. I tried to remove Google Calendar Tab from Tenfourbird (a port of TB to Mac OS X on PowerPC), but it’s still showing up. It’s not in the Add-Ons Manager, but I still have the icon and it still shows under the Tools menu.

    I don’t need it anymore since I’m using CALDAV in Lightning to connect to my Google calendar and Google Tasks Sync.

  26. Hi,

    I have one problem with Google Calendar Tab. Normally, in a browser (I use Firefox), when I’m accessing Google Calendar, I can go to settings and open a second calendar account without closing the first; it just opens in a new browser tab. Your addon allows me to access the same setting, except that when I access the second account, the new tab comes up in the browser, not in T-bird.


  27. Having just switched to Google Calendar Tab after Lightening stopped working, I’m wondering if it’s possible to set it to open automatically as a background tab each time Thunderbird is launched?

    This way any pop-up notifications for tasks or events won’t be missed, as is the case if the add-on isn’t running.

  28. I’ve been using Google Calendar Tab for quite a while and love it. Recently I found it causes Tbird to hang on restart so I’ve had to disable it. I’ve gone thru all me add-ons and sadly it is definitely this add-on that is causing the hang. I guessing it happened on a Tbird update, but I didn’t triage it at the time.

    Anyone else seeing this? Any ideas an what it causing it. I’m currently on 17.0.5.

  29. I can not get an editable version of the tab. It is stuck on “Loading…” with a read-only view option which gets updated. What happened here? Is this the add-on, google calendar or tbird?

  30. I had installed Your Google Calendar Tab to test if about 1 yr ago but normally use the Lightning/Provider addon.
    However now testing the Updated version in Thunderbird 17.0.6 with Linux Kernel 3.7. dual core Centrino w/ 6gb ram.
    What is happening is when I open both the Lightning/Provider in a Tab and then open Your Google Calendar Tab in an adjacent Tab My entire Xfce Desktop Crashes and I am left back a Login Screen.

  31. I love this addon. My only gripe with it is that I use 2-factor authentication with my account and I cannot get Google Calendar Tab to keep in memory that this computer is OK not to use a 2ndary code. Every time I restart TB I have to reenter a code from my phone. Any way to get this to stick?

  32. Any way to choose which google calendar is opened! I added a new account which has now become the default, but I would like to change this to open the old acount ??? any ideas anyone??

  33. Hello,

    Just installed the app on my new Mac with Thunderbird v24 (latest version) but the Google calendar tab did not appear. The URL is correct to my Google calendar. Any help?

    Thanks, Tim

  34. This is a great, simple add-on, and (for me7some users) much better then lightning (as lightning is limited in functionality and kind of compoicated). However, could you make it comaptibel to PostBox. Postbox is a mail client based on TB and has (for me the very important) advantage over TB, to be able to drag and drop multiple emails into finder (on the Mac). It does support TB-Add ons. They have a note to developers here:

    That would be gerat! Thanks a lot!
    best, Urs

    Note to Developers

    Here are a few resources that you may find helpful to your porting efforts:

    Postbox is based on Mozilla Thunderbird, but Postbox is not open-source. But you can find some of the code here (People trying to port Thunderbird add-ons have found this useful.)
    For a version of the DOM Inspector that will work with Postbox 3.0, see
    For a version of the JS Debugger (venkman) that will work with Postbox 3.0, see
    To make an add-on for work for Postbox 3, you’ll need to add this in the extension’s install.rdf file:

  35. I’ve been trying unsuccessfully to get Lightning to work for the last two days, but to no avail. I found this add-on and it works to the extent that my Google calendar events show in the tab, but the font size is so LARGE that I see only half or less of the text in the day boxes. Any ideas???

  36. One problem with your calendar tab and the new google login interface.. If I want to switch google calendars I can no longer simply log out and switch accounts. In internet explorer there’s a “manage accounts” button which is terrible but functional, but in your add-on the only option I have is to “add account” which I don’t want to do.

    So I either need to delete this add-on’s saved data or get the new google login interface working properly. any suggestions?

  37. Hello,
    I Can’t use Lightning because I have an old Thunderbird.
    I made an error: I connect to the wrong google calendar. When I want to change profiles, The link open in Firefox. How can I change the google login in this add-ons ?
    I tried to re-install, the information stay in thunderbird !!!
    Where is stored this login ???

  38. I use Thunderbird with an addon google calendar tab 3.9. Since 2 days this calendar does not automatically open. It advices”Wordt geladen… Voor langzame verbindingen, alleen-lezen weergave laden” so in English this would be something like: “Is loading… for slow connections, load the read-only view”. This stays the case also after reinstalling the addon.
    What is happening?
    Regs, JB

  39. Hi this was great, but it stopped working on 16 March. It will load the read-only page, but not the main page. Tells me my connection is too slow, but its 150Mps as always. Added to Thunderbird 24.3.0. System running Win 7 Home Premium.

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