Problems with time-ago

I’m learning Ruby on Rails and I followed this tutorial:

resulting app: Can be started with Rails 7.0.1 with “rails server” (and I used Ruby 3.1, but older versions should work, too), and then open http://localhost:3000/posts which should show already some test posts (stored in the sqlite database). But the date is not displayed correctly. In the video it says “posted 6 minutes ago”, but in my browser it says for example “Posted February 08, 2022 16:01”. Is there a problem with the timezone or something?

I found the problem: I missed this in application.js:

import LocalTime from "local-time"

I think I wrote it, but then I changed it from the CDN to the downloaded version, and maybe the importmap tool deleted it?