Embedding hypothesis.is

according to this: https://hypothes.is/for-publishers/

I’m supposed to do this:
"To add Hypothesis to your web site, simply add the following line to the HTML source of your page:

"

I’m using the learn2 framework.
I’ve found an index.html, but there’s nothing in it. Where would I paste that ‹script› to have it embedded on all sites? (Including hosted pdf’s that are supposed to be annotated).

Merci beaucoup.

The HTML is generated by the theme. Generally, the HTML <head> tag is defined in user/themes/yourtheme/templates/partials/base.html.twig

this did the trick, thank you!