Quantum

Firefox Quantum

FirePlanet

Nightly Brandrav

EMBL-EBI Theme

A simple theme to give your computer the EMBL-EBI look.

Universe Nebula

Blue Fox Theme

Mail Delivery 4K (2023)

Mail Delivery 4K (2023) theme for Thunderbird 100+ and 4K monitors.

Shirasu Azusa Theme

Adds theme of Shirasu Azusa from game called Blue Archive.

Anime, Blue Archive, Cute, Dark, Game, Shirasu Azusa

Real System Theme

Theme that really follows system colors for Thunderbird 115+.

If you get strange colors instead of what you expect: First switch to the built in system theme, then switch to this theme again.

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.

Jens Theme

Just a theme to enjoy in Thunderbird

Friul

Theme with the official Friulian Flag.

Mail Delivery 4K (2004)

Mail Delivery 4K (2004) theme for Thunderbird 100+ and 4K monitors.

Mail Delivery 4K (2009)

Mail Delivery 4K (2009) theme for Thunderbird 100+ and 4K monitors.

Mail Delivery 4K (2009 Alt)

Mail Delivery 4K (2009 Alt) theme for Thunderbird 100+ and 4K monitors.

Mail Delivery 4K (Grey)

Mail Delivery 4K (Grey) theme for Thunderbird 100+ and 4K monitors.

Mail Delivery 4K (Red)

Mail Delivery 4K (Red) theme for Thunderbird 100+ and 4K monitors.

Mail Delivery 4K (2018)

Mail Delivery 4K (2018) theme for Thunderbird 100+ and 4K monitors.

LSP Theme

Theme for LSP Users.
Added lightsaber at bottom for progress bar in version 1.2

Hatsune Miku (Chrome replica) 4K+

Hatsune Miku, a character featured in vocal synthesis software developed by Crypton Future Media, is one of Japan's most popular manga idols.