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Very nice work, looks great!

I'm raising priority to major since we are without test coverage right now and this is basically blocking any open issues from being merged.

needs a rebase

I resolved the conflicts but the pipelines were failing.
Fixed the phpstan pipeline, composer-lint and some phpcs errors.
There is still a warning in phpcs and phpunit is failing with the error

Unable to install modules: module 'webform_rest_test' is incompatible with this version of Drupal core.

Can someone please look into it.

Thanks @pfrenssen
The changes Look Good To Me.
The pipeline is all green now.
Since i worked on this issue, i wont be able to move it to RTBC
Will wait for someone else to review this

Thanks!