+ $params{content}=~s{
+ (?<![^A-Za-z0-9\s]) # try to avoid expanding non-links
+ # with a zero width negative
+ # lookbehind for characters that
+ # suggest it's not a link
+ \b # word boundry
+ (
+ (?:
+ [A-Z] # Uppercase start
+ [a-z0-9] # followed by lowercase
+ \w* # and rest of word
+ )
+ {2,} # repeated twice
+ )
+ }{[[$1]]}gx;