Select2 field doesn't work when inside a Tab field group

Problem/Motivation

Seems like we cannot place an entity reference field that uses Select2 inside a tabs field group.
The widget loads incorrectly and I get Uncaught TypeError: e(...).select2 is not a function.
Got the same error on Claro and Gin themes.

Steps to reproduce

Using Drupal 9.2.2, PHP 7.4:

1. Install and enable Select2./li>
2. Create a simple taxonomy vocabulary and add a few terms.
3. In a content type, add a field that is a taxonomy term reference to the vocabulary, multiple cardinality. I named mine TOPIC
4. In form display, use widget Select2
5. Add a Field Group Tabs
6. Add a Field Group Tab

Nest it like:

Tabs
--Tabs
---- Your Reference field that uses Select 2 (TOPIC)

Save and try adding a content, should not work:

incorrect screenshot →

Remove the field from nesting, should work:
correct screenshot →

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes