<the literal < (6010 / 748 / 3C16)
\s*any whitespace character, repeated any number of times
Non-Capturing Group(?:/\s*)? ?repeats the group contents below at most once:
/the literal / (4710 / 578 / 2F16)
\s*any whitespace character, repeated any number of times
Non-Capturing Group(?:p|a|strong) pthe literal p (11210 / 1608 / 7016) (case sensitive)
athe literal a (9710 / 1418 / 6116) (case sensitive)
strongthe literal text strong (case sensitive) \s*any whitespace character, repeated any number of times
>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