^start of line
hthe literal h (10410 / 1508 / 6816) (case sensitive)
\d+a digit, repeated at least once
\.+the literal . (4610 / 568 / 2E16) , repeated at least once
\s*any whitespace character, repeated any number of times
.+any character (except for line terminators), repeated at least once
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