\[the literal [ (9110 / 1338 / 5B16)
Non-Capturing Group(?:fi(?:x|nish)ed ?|complete ?)? ?repeats the group contents below at most once:
1st Alternativefi(?:x|nish)ed ? fithe literal text fi (case sensitive) Non-Capturing Group(?:x|nish) xthe literal x (12010 / 1708 / 7816) (case sensitive)
nishthe literal text nish (case sensitive) edthe literal text ed (case sensitive) ?optionally matches the literal (3210 / 408 / 2016)
2nd Alternativecomplete ? completethe literal text complete (case sensitive) ?optionally matches the literal (3210 / 408 / 2016)
#the literal # (3510 / 438 / 2316)
\Kresets the starting point of the reported match. Any previously consumed characters are no longer included in the final match
\d{1,16}a digit, repeated between 1 and 16 times
g modifier: global. Finds all matches instead of stopping after the first
m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string