Some years ago, I managed to find the Auto Message Select (AutoMsgSelect) addon extension on the web, which was originally developed for Thunderbird versions 1.x. The plugin was supposed to select the first message automatically and display it in the message panel.
Since I still use Thunderbird 2.0.0.24, I needed to adopt the plugin for the 2.x product line.

The plugin itself was incomplete, as I found out lately. It did not have the listeners implemented correctly, so the application was unable to select the most recent message, when a new one arrived from the mail server. The plugin also wasn't detecting an ongoing mail server activity, so it always selected a random message among all others.

Well, here is the changelog since v. 1.5.x:

• Automatically selects the most recent (or the oldest) message on startup, or the latest selected one from the previous TB session - you can modify the behavior in the plugin settings.
• Always waits for the mail server to download all new messages, before doing the preselected action.
• Compatible with Mozilla Thunderbird v2.x (maybe even higher, not tested)

Download:

AutoMsgSelect_0.2.3.xpi

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