Proposal is stage 4

README.md

@@ -2,7 +2,9 @@
 
 This is a proposal to add methods like union and intersection to JavaScript's built-in `Set` class.
 
-It is currently at stage 3.
+**It is currently at stage 4: it has been [added to the specification](https://github.com/tc39/ecma262/pull/3306). This repository is no longer active.**
+
+Original readme follows.
 
 ## Proposal
 
@@ -22,6 +24,8 @@ See [details.md](./details.md) for details of current decisions made in this pro
 
 Rendered spec text is available [here](https://tc39.es/proposal-set-methods/).
 
+The proposal was originally authored by [Michał Wadas](https://github.com/Ginden) and later championed by [Sathya Gunasekaran](https://github.com/gsathya) and [Kevin Gibbons](https://github.com/bakkot).
+
 ## Implementations
 
 This proposal is ready for engines to implement and ship. See [this issue](https://github.com/tc39/proposal-set-methods/issues/78) for current status.
@@ -34,6 +38,10 @@ This proposal is ready for engines to implement and ship. See [this issue](https
 * [July 2022](https://github.com/tc39/notes/blob/6f7e075341e435f22777b07a3ee5141442d2d8a7/meetings/2022-07/jul-20.md#set-methods-how-to-access-properties-of-the-argument)
 * [September 2022](https://github.com/tc39/notes/blob/65a82252aa14c273082e7687c6712bb561bc087a/meetings/2022-09/sep-14.md#set-methods-part-iii)
 * [November 2022](https://github.com/tc39/notes/blob/36635060482b1b27bcaff3c950dd9f7b31492dab/meetings/2022-11/nov-30.md#set-methods)
+* [March 2023](https://github.com/tc39/notes/blob/604156b02e312ea2ebd119518fa383efdfb1e646/meetings/2023-03/mar-21.md#set-methods-what-to-do-about-intersection-order)
+* [July 2023](https://github.com/tc39/notes/blob/604156b02e312ea2ebd119518fa383efdfb1e646/meetings/2023-07/july-12.md#set-methods-deferring-callability-check--handling-negative-sizes)
+* [February 2024](https://github.com/tc39/notes/blob/604156b02e312ea2ebd119518fa383efdfb1e646/meetings/2024-02/feb-6.md#set-methods-bugfix-and-update)
+* [April 2024](https://github.com/tc39/notes/blob/HEAD/meetings/2024-04/april-08.md#set-methods-for-stage-4)
 
 ## (Semi)relevant previous discussions