I thought the obj was not defined by default and wrote the definition of the obj separately. Worked.

No problem. It's not very intuitive that posting a comment in a solution (and not marking it as having spoiler content), it'll be visible at the homepage, but that's how it works.

I had no idea about spoiler flag. I will be remember. Thanks!

Use spoiler flag next time.

can you please exaplin how this works?

Thank you

Balkoth is right - it is one of newest JS features.

Yes it's pure javascript, it's from ES6 Template Strings

Hello
Where does the $ come from ? Is it pure javascript ?
I do not find this in the documentation.
Thank you to explain it to me.
Emmanuelle