Tried registering, I usually try the username luc on sites to see if it's still free. But that is an "invalid username", no explanation given. So what, do I nee

Tried registering, I usually try the username luc on sites to see if it's still free. But that is an "invalid username", no explanation given. So what, do I need to add numbers and special characters? Is my legal name too short? Is it already in use? This tells me nothing. Also, the about page is contradictory: > [brain][muscles] one or two emojis instead of avatars > [...] > ASCII only because it works everywhere Hmm hmm, I see. Emojis work so everywhere that I have to [substitute] them to even talk about it here. Seems to me like "we don't do encoding because it's hard" more than because it works everywhere: any device with emoji support will also at least support the basic characters -- perhaps a unicode snowman won't exist in some fonts, but surely a character like µ should work... This is not just about other languages, either: °C, µm, different length dashes, etc. are regular non-ASCII symbols that occur in English. And no, "ASCII only" is not meant in the sense of "plain text only". Any non-US ASCII is converted (ç->c, ÿ->y, ś->s, µ->u).