Update: the favicon is now 'XLM', the currency symbol for Lumens:
What do the letters 'sdf' in the old favicon
stand for?
The letters 'sdf' stand for Stellar Development Foundation, the organization which maintains the Stellar network. Why they are in lowercase can probably only be answered by the Community Managers (employees of Stack Overflow, who maintain this site).
'Stellar' itself would be too long to fit; the risk of using just 's' is duplicating another (possibly future) site in the Stack Exchange network.
IBM
). The convention isn't being followed as much as it used to be, but favicons and site icons tend to be more symbolic than literal, so when I picked the favicon for this site, I was in a lower-case mood... and I went with that.
Jan 17, 2018 at 22:22
XLM
is more consistent with preferring official codes for countries/languages/currencies when they are available. The actual favicon is largely inconsequential, but let me see how hard/easy that is to change after the fact.
Jan 18, 2018 at 14:40