Tooltips not showing, only a question mark is displayed on hover

I cannot reproduce this.

Looks like this is a known issue, the problem is pointing to the correct path to Tippy library.
I'm adding a small patch to fix it.

Unfortunately I still have the same issue. In fact, the tippy js file does not appear to be installed:

$ find . -name "tippy*.js"
./web/libraries/tippyjs/build/css/tippy.js
./web/libraries/tippyjs/test/unit/tippy.test.js

Did I miss something in the library install?

Although this patch didn't help me, it set me on the right track. Not sure how I previously downloaded the webform libraries, but this time I ran "drush webform:libraries:download" and this installed ./dist/tippy.umd.min.js. It's now working, thanks.