Select2 css not applied inside off-canvas because Drupal core reset.css removes it (since Drupal core 10)

Problem/Motivation

Since 📌 Refactor Drupal 10 settings tray / off-canvas to use modern CSS Fixed (Drupal 10) when the Select2 widget is inside the OffCanvas wrapper, select2 doesn't look good.
The reason is that Drupal 10 reset.css removes all select2 styling when placed inside the off-canvas.

See also this ✨ Add a class to opt-out of off-canvas resets in contrib Needs review ticket for a general solution where in drupal core an exclusion class might be added which Select2 can opt-in to.

Steps to reproduce

Proposed resolution

Find a way to render the Select2 widget correctly inside the off-canvas wrapper.

Remaining tasks

User interface changes

API changes

Data model changes