LuxSci

Optimizing Mozilla Thunderbird

Published: December 10th, 2008

LuxSci supports a plethora of modern email programs like Microsoft Outlook and Eudora (our blog posting “Head To Head Battle of Email Clients” discuss several of these) and works with any email program and device that properly supports POP, IMAP, or SMTP.  However, we do recommend Mozilla Thunderbird in the absence of any personal preferences or specific requirements for things that may only be supported in Outlook or other specific programs.  LuxSci’s staff uses Thunderbird with IMAP (or WebMail) uniformly for all email sending and receiving.  We discuss the reasons why in the “Battle” blog article.  Here, we will give some configuration tips and tricks and recommended add-ons.

Thunderbird LogoThis article will focus on the configuration of Thunderbird for IMAP and SMTP; however, many of the things stated for IMAP can also be applied if you are a POP user.  This article is purposely restricted to the features that may be of particular interest to the majority of email users; a great deal has been left out intentionally to keep it relatively short.

Recommended Account Settings

  • Use SSL or TLS (what is the difference?)  Be sure to configure your IMAP and SMTP “Security Settings” to use “TLS” or “SSL” as this protects your username, password, and email from eavesdropping and helps avoid identity theft.  If you are unsure why, see The Case for Email Security.
  • Do not select “TLS, if available”.  This option appears to give you flexibility; however, it opens you up to “man-in-the-middle” attacks where an interloper could insert himself between you and the server. This connection would allow you to connect to a server insecurely (without warning) and thus allow your identity and email to be read.
  • Secure Authentication.  Don’t use this if you are using TLS and SSL, as it will be redundant.  Use this only if you have no option for SSL or TLS and it is available, as it only protects your username and password and does not protect your email messages themselves from eavesdropping and other issues.  In general, if SSL or TLS are not available to you, we recommend that you find another email provider!
  • Under “Advanced Account Settings”, you should uncheck “Show only subscribed folders”.  When you subscribe to a folder, Thunderbird will check it for new email messages.  If you are using “subscriptions” to display folders, what you are really doing is greatly slowing down Thunderbird as it keeps checking all of these folders [that generally are not getting new messages] for new email.  Unchecking this option will cause Thunderbird to show you all of your folders so you can click on any of them anytime you want to see what messages it contains. Not subscribing also allows you to drag and drop messages into them at any time — without impacting Thunderbird’s apparent speed.
  • Under “Copies and Folders“, it is a good idea to configure your “Sent”, “Drafts”, and “Templates” folders to be folders that reside on your IMAP server.  You can only do this once your IMAP account is completely set up and Thunderbird has found your folders on the server.  The advantage of keeping these folders on the server is that (a) they are available from any IMAP-connected computer, (b) they are available in WebMail, and (c) everything in these folders will be visible and “in sync” between all the programs you use to access your email.  Be sure to select the folder names for these that match those used by your WebMail provider and any other email programs also using IMAP with your account — i.e. there is no universal name for the “Sent Email” folder.  A particularly useful feature of Thunderbird is that it allows you to choose to which folder your sent messages should be placed, so that you can utilize the same one that WebMail or your other programs use.
  • Unless you really want to use Thunderbird’s Junk email filtering, we recommend disabling all “adaptive Junk mail controls” under the “Junk Settings” area.  If you leave this enabled, it will slow down Thunderbird as it will be required to download the full content of all messages in your folders in order to scan them and determine if they are Junk or not — and this will happen all the time.  We notice a dramatic speed improvement when the Junk mail controls are disabled.

Local Folders Settings

  • You can edit the location where Thunderbird saves the email stored in your “Local Folders”.  Be sure to put this in a location that is being backed up!  You could even put it on a TrueCrypt encrypted partition or a thumb drive.
  • You will want to disable “adaptive junk mail” controls on the local folders as well (unless you are downloading and saving POP email there and like Thunderbird’s filters).

Thunderbird Options

Thunderbird’s “Options” dialog box offers many very useful settings that can be tweaked to optimize your experience.

  • Tags: Under the “Display” tab, you can edit your “Tags“.  These are “IMAP Keywords” and can be used to both label and color code your email messages.  Use of tags and color coding is a significant feature of Thunderbird, one that is not found on many other clients (like Outlook).  This feature really enhances your productivity when using email. We recommend deleting the default tags (for technical reasons) and creating any new tags that you want to use, defining their colors here as well.  You can also do this in the message list itself.  If you use tags, you will want to show the “Tag” column in the email message list as well.
  • Formatted Email: If you like to send email formatted as HTML (Rich Text) and everyone you know can view such formatted messages because most people can today, then under the “Send Options…” of the “Composition / General” tab, choose “Send the message in HTML anyway” as option of what to do if Thunderbird doesn’t know if the recipient can read HTML messages.  This essentially makes Thunderbird stop asking you what you want to do (i.e. text, HTML or both?) when sending formatted messages.  What if some recipient cannot view HTML-encoded messages?  Add him/her to the text-only list in the same options page.
  • Master Passwords: We highly recommend enabling the “Use a master password to encrypt stored passwords” option in Thunderbird under the “Privacy / Passwords” tab.  If you have Thunderbird save the passwords to your IMAP and SMTP account(s) so that you can login quickly, then anyone sitting down at your computer can open Thunderbird and read your email and send email as you.  With this option enabled, anyone opening Thunderbird will need a special password to cause email to be downloaded or sent.  Additionally, the passwords themselves will be encrypted on disk so that someone else using the same computer cannot “discover” them (even if they have administrative access to your machine).  On a related note, the Mozilla FireFox web browser also has the same feature for securely saving the passwords that you use on web sites.  For more information, see: Master Password Encryption in FireFox and Thunderbird.
  • Automatic Updates: Under the “Advanced / Update” tab … be sure that Thunderbird is configured to automatically check for updates.  This will protect you in the case that problems with Thunderbird are discovered and fixed.

Some Recommended Add-Ons?

One of the characteristics of Thunderbird that makes it such a great client is the “add-on” infrastructure, where you can install any one of hundreds of extensions that have been created to add interesting and useful features to Thunderbird.  You can browse the ad-ons here.  Some of the ones we have found that might be particularly useful include:

  • Enigmail – Adds PGP email encryption, decryption and digital signatures to Thunderbird. (S/MIME-based encryption comes built in). See this article on how to set this up.
  • Lightning — Calendars and Tasks in Thunderbird; supports WebDAV and CalDAV
  • Tag Toolbar — Makes it even easier to tag messages with your custom tags.
  • MozPod — Synchronize Thunderbird contacts and calendars with your iPhone
  • SmartSave — Export your local and IMAP folders from subfolders easily.
  • ThunderBrowse — View and browse web sites from within Thunderbird.
  • QuickFolders — View your favorite folders as tabs so you can switch between them and drag messages to them easily

At LuxSci, we do not use any of these universally and do not support them, but have found them useful for various purposes.  To install an add-on, click “Tools > Add-ons” from the Thunderbird menu. Then click on the “Install…” button and choose an add-on file that you have downloaded from one of the above links (or any others that you have downloaded).

Other Tips and Tricks

Here are some other tips and tricks that you may find useful:

  • Columns: You can change what columns are displayed in your email list by clicking on the little icon to the right of the headings list.  Use this to remove the columns you don’t care about and to add ones that perhaps you do (like “Tag”)
  • Arrangement: You can re-arrange the order of the columns and their sizes by dragging and dropping the columns and the dividers between them.
  • Recycling Email: If you want to re-send an email message, select it and use the “Message > Edit as New Message” command.  This essentially allows you to treat any messages in any folder like a saved draft.
  • Saved Searches: You can save your searches as virtual folders so that you can access simplified views of your email folders more quickly in the future.
  • Folder Management: Do not create subfolders of your “INBOX” if you have a non-empty “IMAP Folder Path” as Thunderbird will not save these subfolders in the correct place (it will save them under “folder path/INBOX/subfolder”.
  • If your email provider supports folders that can contain folders, we recommend using nested folders to better organize your email.  This will be cleaner and easier to deal with than having all folders “at the top level”.
  • Signatures: To use an email signature that is formatted in HTML (rather than being treated as plain text), save the HTML signature content to a file that ends in “.html”.  Then, specify this file as your signature.  Thunderbird determines the content type of the signature based on the file extension.
  • Compact Speed Up: If you “mark your messages as deleted” and then “compact” your folders, as is one common way of managing email, we recommend that you compact by right clicking on the folder to be compacted and choose “Compact” from the pop-up menu.  This will compact just this folder and will be pretty quick.  If you choose “Compact Folders” from the “File” menu, Thunderbird will try to compact ALL of your folders … this can be very slow and can impact Thunderbird’s apparent performance.
  • Size Matters: Keep the size of your INBOX and other frequently viewed folders (especially any subscribed folders) small.  This will improve performance overall.  Thunderbird can easily handle very large folders, but small folders are quicker and easier for any email program and for the server as well.
  • Forced use of 256-bit AES with SSL/TLS:  If you are very security conscious or have a requirement for using only 256-bit AES encryption when connecting to your email, you can configure Thunderbird so that this is the only encryption mode that it will use.  See: “256-bit AES Encryption for SSL and TLS: Maximal Security“.

We hope that you found our tips and tricks and configuration ideas useful.  We’ll update this post and publish more ideas in the future.

5 Responses to “Optimizing Mozilla Thunderbird”

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    […] feature available from most providers.  Only LuxSci WebMail, and a few email clients, such as Mozilla Thunderbird, support email […]

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    […]  Mozilla Thunderbird (v2): (see also optimization tips for Thunderbird) […]

  4. Master Password Encryption in FireFox and Thunderbird | LuxSci FYI Says:

    […] you are allowing Mozilla FireFox or Thunderbird to remember passwords to web sites and/or email accounts in their Password Manager tool, you should […]

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    […] Most people send mail in two ways – with a web-based interface like Yahoo! or Gmail, or with an “email client” program like Outlook or Thunderbird. […]

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