Rated 1 out of 5 stars
This extension no longer works at all in Thunderbird at ver. 11.0.1. If this extension is still being maintained, it would be nice if the author would update it.This review is for a previous version of the add-on (2.0.2). This user has a previous review of this add-on.
Please test if version <a href="https://addons.mozilla.org/thunderbird/downloads/file/148471/compactheader-2.0.3beta3-tb.xpi">2.0.3beta3</a> fixes your problem