Try this add-on:

https://addons.mozilla.org/en-US/thunderbird/addon/deselect-on-delete/

I presume your workflow is based on the common misconception that it's dangerous to open dubious-looking messages.

I'd argue that if you're opening messages in their own tab or window, then you cannot see what will open next. That seems to me to be (potentially) a lot more dangerous then reading messages in the message pane directly below the thread pane, where you can see exactly what will open next.

In any case, opening messages in Thunderbird is safe. It will not and can not run scripts in email messages. By default remote content is disabled.

I have never used the next or next unread buttons or keystrokes. It feels to me too much like driving a car in the dark, in the fog, on ice, with no headlights and no brakes. You can't see what's coming up and you can't do anything about it when you do encounter it.

> I presume your workflow is based on the common misconception that it's dangerous to open dubious-looking messages.

Based on years of using Outlook Express and then Windows Live Mail, yes. You're right though, Thunderbird does prevent all the things those didn't, which can be annoying at times, but is ultimately appreciated.

However, I am so used to that whole layout that this is how it will continue. I inadvertently closed Thunderbird three times before I finally went looking for a way to open messages in their own window rather than in a new tab.

The message window is shorter than the Thunderbird window, so I can see the new messages below it. I also usually scan my new messages before opening any, to find the crap and delete and also to read the important ones first. So there is no danger of opening something "blindly" - by the time I am reading them, I already know I want to open all of them.

But according to the description on this add-on, it won't solve my problem. It says it prevents selection of the next message, but I want to select the next message. I don't want to select the last message, that I just read. And in that regard, Thunderbird already has a setting that does not select any message after deleting the current one (in Options|Display|Advanced), so this add-on is unnecessary.