It has reached stage 4. https://github.com/tc39/proposal-duplicate-named-capturing-groups https://arai-a.github.io/ecma262-compare/?pr=2721
It has reached stage 4.
https://github.com/tc39/proposal-duplicate-named-capturing-groups
https://arai-a.github.io/ecma262-compare/?pr=2721