A bit like Gmail/Outlook look&feel, based on chrissi4u's 'CLEAN ADAPTION no1' designed for vertical message view. Note that you will have to adjust the width of the panes for the message list to display correctly AND you should arrange the columns in the following order: STARRED, ATTACHMENTS, SUBJECT, SENDER, DATE, SIZE. Or you can experiment with those. Not guaranteed to work with every window manager.
A very cleaned-up style for the User Interface only. Inspired by Material design, Outlook and Postbox. Affects the main-interface and the calendar/lightning add-on. Detailed description and comments inside the CSS. Please read the additional information here, or the one inside the code. Updated (1) 15.Dec.2015 - force white titlebar also with cuxtom visual styles.
Dark theme for Thunderbirds main UI. If you have any issues with this style, please open a ticket at https://github.com/NiklasGollenstede/stylish
Really wanted a clean dark theme, but no good ones that I liked existed. Created this and realized how easy (and a bit of a pain) it was to make one. This includes a slightly modified Twister's Labels. Hope you enjoy!
Thunderbird tabs without curves and gradients
Gets Thunderbird more fit with Windows 8 and Windows 10 looks - sharper tabs, fewer gradients. Customizable.
A remix of Thunderbird Darkning by BastienHo.
For people who use the awesome Numix Dark theme for Linux. This userstyle fixes Thunderbird's horrible appearance if you use Numix Dark. If you want to know what parts of Thunderbird are changed: Screenshots speak louder than words, so check them out.
A dark view of thnderbird conversation, for use with a dark theme On the screenshot, I also use accountColor
Some Opera-inspired adjustments of a particular "square tab" theme to fit with Windows 10 better.