Hello !
I tried to implement the social share buttons from Finsweet on a CMS page.
But it doesn’t work on all platforms (Linkedin, Facebook and URL), I don’t know why.
Is it because my website is not indexed ?
I ran tested with the attributes support : the implementation is OK.
On Linkedin, there is an error message (not possible to display the + it doesn’t display the link.
I can share with you a link on a ‘test’ project (static page).
Thanks for your help 
Here is my site Read-Only: Webflow - EXERCISES
(how to share your site Read-Only link)