Email field falls outside group on core contact form

I've installed a boilerplate version of drupal 8.8 using docksal
Installed 3.0.0-rc2 of field_group using composer

I've created 2 groups left_side and right_side on the website feedback form under admin/structure/contact

I've placed name and email in the left_side and subject and message into the right.

Viewing the form it looks like this

I would expect the email field to reside in the email group but it does not?

Reverting the code base back to 8.x-3.0-beta1 I can see that this broke in 8.x-3.0-rc1