Once Bug 1795452 lands, we'll need to decide when we ship the feature on nightly.

I think a good requirement would be having test262 tests available for it.

Igalia is planning to start on test262 tests soonish, fwiw.

MDN Tracking bug: https://github.com/mdn/content/issues/22145

Depends on D178474

Depends on D178481

Backed out for causing multiple failures on test_xrayToJS.xhtml.

• Push with failures

• Failure log

• Backout link

[task 2023-05-23T21:32:38.243Z] 21:32:38     INFO - TEST-PASS | js/xpconnect/tests/chrome/test_xrayToJS.xhtml | Xrayed instances see proto expandos 
[task 2023-05-23T21:32:38.244Z] 21:32:38     INFO - Buffered messages finished
[task 2023-05-23T21:32:38.245Z] 21:32:38     INFO - TEST-UNEXPECTED-FAIL | js/xpconnect/tests/chrome/test_xrayToJS.xhtml | A property on the Array constructor has changed! You need a security audit from an XPConnect peer - got "[\"from\", \"fromAsync\", \"isArray\", \"length\", \"name\", \"of\", \"prototype\"]", expected "[\"from\", \"isArray\", \"length\", \"name\", \"of\", \"prototype\"]"
[task 2023-05-23T21:32:38.246Z] 21:32:38     INFO - SimpleTest.is@chrome://mochikit/content/tests/SimpleTest/SimpleTest.js:507:14
[task 2023-05-23T21:32:38.246Z] 21:32:38     INFO - testXray@chrome://mochitests/content/chrome/js/xpconnect/tests/chrome/test_xrayToJS.xhtml:501:7
[task 2023-05-23T21:32:38.247Z] 21:32:38     INFO - testArray@chrome://mochitests/content/chrome/js/xpconnect/tests/chrome/test_xrayToJS.xhtml:648:13
[task 2023-05-23T21:32:38.247Z] 21:32:38     INFO - go@chrome://mochitests/content/chrome/js/xpconnect/tests/chrome/test_xrayToJS.xhtml:185:5
[task 2023-05-23T21:32:38.247Z] 21:32:38     INFO - onload@chrome://mochitests/content/chrome/js/xpconnect/tests/chrome/test_xrayToJS.xhtml:1:1
[task 2023-05-23T21:32:38.249Z] 21:32:38     INFO - TEST-PASS | js/xpconnect/tests/chrome/test_xrayToJS.xhtml | A symbol-keyed property on the Array constructor has been changed! You need a security audit from an XPConnect peer 
[task 2023-05-23T21:32:38.249Z] 21:32:38     INFO - Running tests for property: Array.from

Backed out for causing failures at from_async.js

Backout link: https://hg.mozilla.org/integration/autoland/rev/1c427c471f76950cdd4446c672397f205789d3c5

Push with failures: https://treeherder.mozilla.org/jobs?repo=autoland&resultStatus=testfailed%2Cbusted%2Cexception%2Cretry%2Cusercancel&revision=c717912156f584e9cf021cbbe7c9545a7da9748f&selectedTaskRun=YjMX8AZwRU2u5FIOMIbD2g.0

Failure log: https://treeherder.mozilla.org/logviewer?job_id=417018859&repo=autoland&lineNumber=3884

https://hg.mozilla.org/mozilla-central/rev/7c2aa1e8b112
https://hg.mozilla.org/mozilla-central/rev/c717912156f5

Backout merged to central: https://hg.mozilla.org/mozilla-central/rev/763f7f02601be7c0c12b72e92d1b8afd8b759582

https://hg.mozilla.org/mozilla-central/rev/1ddd8a91b473
https://hg.mozilla.org/mozilla-central/rev/89d5831aba4a

FF115 MDN docs work for this done - essentially just compatibility data update, MDN release note, and removal of experimental tagging on API.
See https://github.com/mdn/content/issues/22145