\b assert position at a word boundary: (^\\w|\\w$|\\W\\w|\\w\\W)
1st Capturing Group (\w+?)
\w+?
matches any word character (equal to [a-zA-Z0-9_])+? Quantifier — Matches between one and unlimited times, as few times as possible, expanding as needed (lazy)
\1 matches the same text as most recently matched by the 1st capturing group
\b assert position at a word boundary: (^\\w|\\w$|\\W\\w|\\w\\W)
g modifier: global. All matches (don't return after first match)