Rated 4 out of 5 stars

Very nice Add-on. Please update it for TB13. It is too much work to close Thunderbird, search the Thunderbird \extension folder, copy the matching (Classic Reloaded)*.xpi to another folder with enough access-rights, open the *.xpi with 7Zip, open the install.rdf inside the *.xpi, change the line to the actual TB-Version, like <em:maxVersion>13.*</em:maxVersion>, save the install.rdf back to the *.xpi, copy the *.xpi back to the \extension folder, drag&drop the *.xpi to the restarted Thunderbird-Add-ons-Manager (openend in a new tab).
Thank you!