(?s)applies the following effective flags to the remainder of the pattern: gms s modifier: single line. Allows a dot to match line terminators
^start of line
interfacethe literal text interface (case sensitive) \ba Unicode word boundary
.+?any Unicode character, repeated at least once
\r?optionally matches a carriage return (ASCII 13)
\na line-feed (newline) character (ASCII 10)
=+the literal = (6110 / 758 / 3D16) , 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