<the literal < (6010 / 748 / 3C16)
\d+a digit, repeated at least once
>the literal > (6210 / 768 / 3E16)
\h*any horizontal whitespace character, repeated any number of times
\d+a digit, repeated at least once
Non-Capturing Group(?:\.\d+)? ?repeats the group contents below at most once:
\.the literal . (4610 / 568 / 2E16)
\d+a digit, repeated at least once
\h*any horizontal whitespace character, repeated any number of times
\h*any horizontal whitespace character, repeated any number of times
\1the text saved by group 1
>the literal > (6210 / 768 / 3E16)
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