Vue.js DevTools extension for Chrome does not detect Vue in the course files

[toddprouty]

When viewing the course files in the latest version of Chrome (Mac), Vue.js is not detected by the Vue.js DevTools extension.

Steps to reproduce

This assumes you're using VS Code with the Live Server extension installed, though the results may be the same in other editors with a live server view.

1. Download/clone.
2. Open index.html in VS Code.
3. Open with Live Server (use the command palette or right-click in the file and select the option).
4. Note that the extension icon does not light up to indicate that Vue.js is detected. When you click it, it should say "Vue.js not detected."
5. Open DevTools and note that the Vue menu item is not present.

This is resolved, as described here, by both installing the beta version of the extension and replacing the library reference. Updating the course files would of course do the trick as well. (If I get time I'll submit a pull request.)