we’ve got a new adventure to explore for you: Bootstrap 5 will be default from the next major version on (6.5.x).
Until then, Bootstrap v4 still remains default. The new Bootstap 5 possibilities will stay behind a feature flag till then .
To learn more, please check out this blog post:
For the impatient ones, here is the direct link to upgrade.md
Take a look, play with all the new opportunities and prepare your storefronts and extensions for the future!