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Abstract Theme Carole Pepper
An abstract Firefox theme of the charactor Carole Pepper of Honkai Impact 3rd. Inspired by the color of the character's default skin, including the character's skin tone and clothing color. The copyright owner of the charactor Carole is Mihoyo.
Dark electric violet
Dark and violet theme for Thunderbird by Stonymontana
summersmile
Summersmile adds a lively flair to Thunderbird with a sunny yellow background, playful smiley graphics, and a "sunshine and smiles" theme that refreshes your email experience.
Valorant Red
A Thunderbird theme version with custom 'Valorant'-red CSS
Real System Theme
Theme that really follows system colors for Thunderbird 115+.
Rose Pine Dawn
A theme based on the Rose Pine Dawn color scheme (https://rosepinetheme.com/)
Shirasu Azusa Theme
Adds theme of Shirasu Azusa from game called Blue Archive.
Anime, Blue Archive, Cute, Dark, Game, Shirasu Azusa
Tiger eyes turquoise (light theme alt)
A light theme of a gray toned tiger with turquoise eyes.
This is a modified version of the theme "tiger eyes light blue" from AmSumz.
Muted Sage Gruvbox Dark
Muted Sage Gruvbox dark theme for Thunderbird.
Forked from calvinchd's gruvbox dark theme.
Endless Stars
My first Endless Stars Thunderbird Theme with Twinkling Stars. The only thing missing is the falling star animation.
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