1,$s/Alpen/Muesli_Of_Choice/g
So WTF does it actually mean? That you'd pay $1 for Alpen cos it's your muesli of choice?
It's a command string used within an UNIX editor called vi, or a command line string processor called sed.
The first bit "1,$" specifies a range of lines; from line 1 (the first line) to (,) line $ (or the last line). In other words, over the entire bit of text (which, in context, would mean the posters original/previous post).
Over that range of lines, perform the following action:-
s(ubstitute) the first occurrence on each line of the string "Alpen" with the string "Museli_Of_Choice". The first character after the s (a forward slash / in this case) is used as the delimiter of the two strings. This could have been anything that doesn't occur in either of the two strings (or if it did occur it would need to be escaped with a preceeding backslash).
The trailling g modifier forces the substitution to take place for subsequent string matches on each line, rather than just the first on each line. Just in case it occurs more than once on each line.
In other words, it's sed/vi speak for "OK, replace every occurrence of Alpen with Museli_Of_Choice".
Translated it pretty much means "OK, don't be a fuckwit and ignore what I said purely because I said Alpen instead of whatever brand of Museli you do eat, imagine I picked the name of whatever brand of Museli you do eat and respond to my point like an adult."
Although the original author may not have implied as much bile as that in their original post.
HTH.
