… because one also cares about beauty… a default avatar picture is not an option… but phpBB has a very strict 6KBytes max file size limit for Profile Avatar Pictures…  which is almost impossible to reach with format.jpg or format.png … but with a reduced color palette and GIF the user can do it! 🙂

tux badge as png: (19KBytes)

the same tux badge as gif (2.7KBytes)