I've been using mozilla email clients for 9 years now over which time they haven't changed much, and this new release of thunderbird is no exception. The most significant thing about this release is that mozilla have directed some resources towards the email client which has until recently languished without much care and attention.

The screenshot above shows thunderbird in a vertical layout which I've decided to try in conjunction with this new version, as previously I used the "classic" layout. You can see in the left pane that both my email and news feeds are handled by thunderbird, which includes my twitter messages as displayed in a per folder customized view below.

Installation

I upgraded from thunderbird 2 but unfortunately there were no v3 packages available for my linux distro, and mozilla themselves don't release linux builds in standard linux packages for some reason. They should should take a leaf out of Google's book here and look at how they release the chrome beta for linux, which coincidentally was released on the same day as thunderbird 3. I extracted the thunderbird release tarball to /usr/local/thunderbird/ to supersede the official one for my distro. Upon running it though I was disappointed to find it didn't pick up my existing mail and settings. Some investigation revealed that ubuntu use ~/.mozilla-thunderbird/ as the profile directory rather than the standard ~/.thunderbird/, so after renaming that directory I was happy to see all the old settings honoured. I also notice there will be improved migration from V2 to V3 in V3.1. As for plugins I only use a couple. The existing "Remove Duplicate Messages" plugin was not compatible with the new thunderbird, but there is a new version which is, and is faster and less buggy to boot (the old one intermittently crashed the whole client).

Improvements

Not much to report here TBH.

• One can now customize the fields displayed on a per folder basis which is handy as demonstrated with the twitter screenshot above.
• Emails, and email folders can be opened in separate tabs. I don't use this actually as it would only slow down my workflow when switching tabs. I guess this may be useful in conjunction with plugins like thunderbrowse or calendaring, which I don't use.
• There is a new "Smart Folder" mode where special folders (Inbox, Sent, ...) from multiple accounts are displayed as one. Again I find this only marginally useful and so don't use it
• One can at last delete collapsed threads, not just the top message! This fixes the bug I logged 9 years ago!

Issues

There is nothing to preclude me from using the new version but there are a few issues.

• The interface still becomes unresponsive when RSS feeds are being updated, even though the thread count has increased from 13 to 19 over version 2
• RSS content is not displayed until restart, if the layout was changed. See bug 531397
• The colour used to highlight folders with new mail is wrong, particularly on ubuntu. See bug 523972
• The "content-transfer-encoding" email header item was displayed which was ugly. See bug 517593
• Related to the new functionality of being able to set displayed fields independently for each folder, one can't however change the default set of fields to display, or copy settings to multiple folders. See bug 505035
• Undeleting a feed item, or resubscribing to a deleted feed folder, requires removing items from feeditems.rdf. See bug 518647
• There are flipping stars everywhere

See also avoid thunderbird interface delays.