Is `Rule` keyword supported?

I've looked into the [spec][1] and all [test data][2] and couldn't find any mention of `Rule` support. Did I miss something or there is only `Gherkin 5` support? Is it planned to support `Gherkin 6`?

[1]: https://github.com/cucumber/cucumber-json-schema/blob/main/schema.json
[2]: https://github.com/cucumber/cucumber-json-testdata-generator

Start by reading schema.json and comparing it with the linked cucumber-json-testdata-generator data. Check how Gherkin 5 constructs are represented and whether the available data shows a Rule construct. Done means the project’s support for Rule and Gherkin 6 is documented or clearly defined in the schema and test data.

Written by the indexing model from the issue text.