^start of line
\d{4}a Unicode decimal digit, repeated exactly 4 times
/the literal / (4710 / 578 / 2F16)
\w{3}a Unicode word character, repeated exactly 3 times
/the literal / (4710 / 578 / 2F16)
\d{2}a Unicode decimal digit, repeated exactly 2 times
the literal (3210 / 408 / 2016)
\da Unicode decimal digit
\da Unicode decimal digit
:the literal : (5810 / 728 / 3A16)
\da Unicode decimal digit
\da Unicode decimal digit
:the literal : (5810 / 728 / 3A16)
\da Unicode decimal digit
\da Unicode decimal digit
\.the literal . (4610 / 568 / 2E16)
\d+a Unicode decimal digit, repeated at least once
the literal (3210 / 408 / 2016)
Group 1(.*(?:\n(?!\d{4}/\w{3}/\d{2}\b).*)*) .*any Unicode character (except for line terminators), repeated any number of times
Non-Capturing Group(?:\n(?!\d{4}/\w{3}/\d{2}\b).*)* *repeats the group contents below any number of times:
\na line-feed (newline) character (ASCII 10)
Negative Lookahead(?!\d{4}/\w{3}/\d{2}\b) \d{4}a Unicode decimal digit, repeated exactly 4 times
/the literal / (4710 / 578 / 2F16)
\w{3}a Unicode word character, repeated exactly 3 times
/the literal / (4710 / 578 / 2F16)
\d{2}a Unicode decimal digit, repeated exactly 2 times
\ba Unicode word boundary
.*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