Currently when you use capture groups, only the ones that were found are shown in the result, and others are omitted. So it's hard to tell which capture group something belongs to without doing a regexMatch again, which could probably be slower

"abc" regexFind ["(d)|(b)|(c)", 0];
// sample return
[[["b", 1],["b", 1]],...]

so having a new optional parameter that returns all capture group results (empty ones as []) is useful:

"abc" regexFind ["(d)|(b)|(c)", 0, true];
// sample return
[[["b", 1], [], ["b", 1], []],...]