Why bootstrap is loaded from node module and not from libraries.yml like Barrio? (bug with the navbar)

I was getting this same error with the navbar and they weren't opening or closing. After much head scratching found out that the popper.js file had not been included in the libraries.yml file when I created my subtheme. The bootstrap.bundle.min.js, I'm guessing includes popper.

So for anyone that is also having issues check that you have the below file structure in libraries.yml and are not missing the popper.min.js file:

global-styling:
version: VERSION
js:
js/popper.min.js: { weight: -49 }
js/bootstrap.min.js: { weight: -48 }
js/barrio.js: {}
js/custom.js: {}

If you landed to this page due to issues with dropdowns in the navbar, here is the cause of the problem and possible solutions.

What is the causing the issue?

For the dropdown to work, bootstrap uses a third party library popperjs. In the THEME.libraries.yml file of `SASS Starter Kit`, this library is missing which is causing the issue.

To fix it,

Use bootstrap.bundle.min.js instead of bootstrap.min.js . The bootstrap.bundle.min.js file includes popperjs library and thus solves the issue. You can use a CDN link(//cdn.jsdelivr.net/npm/bootstrap@5.2.0/dist/js/bootstrap.bundle.min.js) in your THEME.libraries.yml file.

As mentioned by @GazzaT in #3 💬 Why bootstrap is loaded from node module and not from libraries.yml like Barrio? (bug with the navbar) Needs review , adding js/popper.min.js: { weight: -49 } to the THEME.libraries.yml solves the issue.

Make sure to keep the weight -49 or lesser because popper.min.js needs to loaded before bootstrap.min.js. From the bootstrap docs,

If you decide to go with the separate scripts solution, Popper must come first (if you're using tooltips or popovers), and then our JavaScript plugins

.

I would prefer because it is a modular approach and lets us exclude it(popperjs) if not required.

#3 solution is working for me. Creating patch for this solution.

Thank you for posting this. Adding text strings for toolbar and admin_toolbar to help others find it. I spent many hours debugging before actually figuring out a related issue.

The solution according to the patch has already been applied on Branch 5.x latest release.