Rated 5 out of 5 stars

by Charles Taylor on May 16, 2011 ·

OK, this time there's a real replacement.

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

Rated 5 out of 5 stars

by Charles Taylor on Aug. 31, 2010 ·

I used this extension for years and refused to update T-bird when a replacement was not available. I finally found a replacement. The extension Mail Tweak has a preference for "Deletion Behavior". The setting "nothing" does the same thing that Unselect Message did. It has a bunch of other cool tweaks too. The Mail Tweak extension is at Mozdev ... http://mailtweak.mozdev.org/.