^start of line
\[the literal [ (9110 / 1338 / 5B16)
\d{2}a Unicode decimal digit, repeated exactly 2 times
/the literal / (4710 / 578 / 2F16)
.*any Unicode character (except for line terminators), repeated any number of times
Non-Capturing Group(?:\n(?!\[\d{2}/).*)+ +repeats the group contents below at least once:
\na line-feed (newline) character (ASCII 10)
Negative Lookahead(?!\[\d{2}/) \[the literal [ (9110 / 1338 / 5B16)
\d{2}a Unicode decimal digit, repeated exactly 2 times
/the literal / (4710 / 578 / 2F16)
.*any Unicode character (except for line terminators), repeated any number of 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