FOSSwire

Extensions are one of the major selling points for Firefox. No other browser can match the sheer volume of third-party mini applications and enhancements.

Most Firefox users are aware of the concept of extensions, but not as many people know that Extensions (and Themes) are available for its email client cousin Thunderbird as well.

First of all, head over to the Thunderbird Add-ons site in your web browser. It is almost exactly the same as the Firefox Add-ons site and works in largely the same way.

For the purposes of this post, I'll download and show you how to install Lightning, which is an extension for Thunderbird that gives it full calendar functionality, which you may like if you are used to using a more integrated PIM environment such as Microsoft Outlook.

The major potential pitfall is in the downloading stage. Unlike Firefox add-ons, you can't just click the download button to download and install the file. If you do so, Firefox will try and install the extension, even if it is meant for Thunderbird.

Instead, right-click the file and use Save As. You will end up with a file with a .xpi extension, which we now bring manually into Thunderbird.

Once the file has downloaded, go into Thunderbird and choose Tools > Addons. In recent versions of Thunderbird, you can simply click the Install button in this window, locate the file and then install and restart the program like normal.

On older versions of Thunderbird, you'll need to leave this Add-ons window open, then drag the file from a file manager across and drop it in the window. You should get the same Install dialogue and be up and running!

If you are a Thunderbird user, it's easy to forget that it shares the same extensibility as Firefox does, so head on down to the Add-ons page, try some out and find the ones you like!

If you're experimenting with Linux, or even moving over to it and you're currently using Thunderbird as your email client on Windows, you might be wondering how to move your emails and profile from Windows over to Linux.

This process can even be used as part of a bigger project, for example to move from Outlook Express or another Windows-only email client on Windows to Thunderbird on Linux. If you first Import from your Windows client to Thunderbird on Windows, you can then follow this tutorial to move that over to Linux. But anyway, let's get on.

The first thing I recommend doing isn't essential, but can prevent headaches later. In your Windows copy of Thunderbird, go to File > Compact Folders. This cleans your mail folders up and can prevent issues with unread counts not being correct once your profile folder has been migrated over.

The process is reasonably simple, provided you know where your profile folder is on Windows and can transfer the files somehow between Windows and Linux. To find your profile folder, follow the instructions on this page that pertain to the version of Windows you are running.

Once you've found that profile folder (and you're inside Thunderbird > Profiles), there should be a randomly named folder ending with .default. Copy this folder somehow to your Linux machine.

Over on Linux, we first need to remove any existing profile information for Thunderbird if you've opened it already. Obviously, make sure you're not actually using Thunderbird on this user account for anything important, or this step will end up deleting all your email there. You have been warned.

Go into your home folder on Linux, and choose View > Show Hidden Files. If you've already opened Thunderbird, there will be a folder called .thunderbird (Debian and Ubuntu users, .mozilla-thunderbird). Delete it - as long as you're sure there's nothing important there.

Now (re)create that folder, so right-click, Create New Folder and name the folder .thunderbird, or .mozilla-thunderbird on Debian/Ubuntu. Go inside your new folder and paste your profile folder that you copied from Windows.

There is one final step you need to take to get your mail up and running in Linux. Inside .thunderbird, you need to make a file called profiles.ini. Do a right-click and create a new text file in the folder, and name it profiles.ini. Open up this new file in a text editor, and paste in the following:

[General]
StartWithLastProfile=1
[Profile0]
Name=default
IsRelative=1
Path=xxxxxxxx.default

Replace the xxxxxxxx with the real name of your profile folder that you pasted. Save the file and quit, and now launch Thunderbird. Your email should load up as if nothing has happened and all your archives should be up and rolling.

Should you run into any problems with folder unread counts being incorrect as I mentioned above, you'll have to go through the affected folders, mark items so that the unread count is correct again, then perform File > Compact Folders to force those changes to save to disk, or the problem will reoccur.