1. Go to https://mailchimp.com
2. Create an account
3. Wait for the confirmation email
4. At a point the user is redirected to https://us5.admin.mailchimp.com/signup/setup/

The page fails with "an error occured"

When trying to diagnose a bit, we can see that the error is created by a RangeError.

and when running a mozregression, we get

19:27.49 INFO: Last good revision: d49d84396d57671c34657fa3bac0e385d6d07f70
19:27.49 INFO: First bad revision: 7f44a968af7fd604fc13de9a398dec4ce8ebebd2
19:27.49 INFO: Pushlog:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=d49d84396d57671c34657fa3bac0e385d6d07f70&tochange=7f44a968af7fd604fc13de9a398dec4ce8ebebd2

Which points to Bug 1648137

This was reported as a webcompat issue.
https://webcompat.com/issues/90899

It is happening in
https://us5.admin.mailchimp.com/release/1.1.12d10d170ea6367f…c4b36527f925bfd6e967169d/js-src/main.d2683f73469112c2ec6b.js

invalid value \"true\" for option useGrouping

at a point the code is reaching

    var a = {
      style: 'decimal',
      useGrouping: 'true'
    };

Thanks for the report! I've filed https://github.com/tc39/proposal-intl-numberformat-v3/issues/74 at the proposal repository.

Set release status flags based on info from the regressing bug 1648137

The feature which introduced this bug is Nightly-only, therefore I'm resetting the status fields for now.

(In reply to André Bargull [:anba] from comment #3)

The feature which introduced this bug is Nightly-only, therefore I'm resetting the status fields for now.

Is this still Nightly-only? Could you mark this bug as blocking the bug to enable this feature?

Updates GetStringOrBooleanOption per https://github.com/tc39/proposal-intl-numberformat-v3/pull/9.

We don't yet have a bug to enable this feature by default, but instead we can just fix the regression, now that the proposal has been updated.

https://hg.mozilla.org/mozilla-central/rev/9e042f230960