PNG ICO ICNS MORE
Desktop apps
3D
Mozilla icons
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256x256
Handdrawn
Sketchy Icons v 1.2
Copy, Thunderbird
Smooth
170 dock icons
Cartoon
Puck icons pack II
mozilla, Thunderbird
300x300
3D Cartoon Icons Pack
Artcore
512x512
iSuite Revoked
Orb icons
Thunderbird, mozilla
128x128
3D Cartoons III
KDE Crystal Diamond
22x22