Assegnate 5 su 5 stelle

Thanks for the Calendar colour fix. So 5 stars now.
This is a very nice, uncluttered dark theme.

Questa recensione riguarda una versione precedente (4.0) del componente aggiuntivo. 

Hello. fixed. Please, download new version of Dark Night Arcturus X (4.1) from my private Add-on home page (https://www.yonak.pl/tbthemes/) or wait a few days for approval it by Mozilla and then update the theme directly in Thunderbird, @nyquisteroux