Thunderbird has just updated & I've lost my night mode screen. Settings isn't coming up (on the 3 bars) as a choice | Thunderbird Support Forum | Mozilla Support
The Best Thunderbird 65+ Light & Dark Themes (2020) | RH
Darko :: Add-ons für Thunderbird
How to Enable Dark Theme in Mozilla Thunderbird
Thunderbird 60+ Dark Theme Improvements · GitHub
Mozilla Thunderbird: DeepDark-Addon macht Dark Mode möglich