\d+a Unicode decimal digit, repeated at least once
%the literal % (3710 / 458 / 2516)
Negated Character Class[^.] .the literal . (4610 / 568 / 2E16)
Non-Capturing Group(?:(?!original\b)[^\d\r\n])* *repeats the group contents below any number of times:
Negative Lookahead(?!original\b) originalthe literal text original (case sensitive) \ba Unicode word boundary
Negated Character Class[^\d\r\n] \da Unicode decimal digit
\ra carriage return (ASCII 13)
\na line-feed (newline) character (ASCII 10)
\ba Unicode word boundary
percentagethe literal text percentage (case sensitive) \ba Unicode word boundary
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