Normally, you should see a ‘Save to Library’ button in the Chrome extension when you are logged into your Scholarcy Library account. If not, you may need to log out from Scholarcy Library, clear your cookies, and log in again.
Log out from your Scholarcy Library. Go to chrome://settings/siteData?search=cookies and search for scholarcy.com. Delete cookies from app.scholarcy.com and scholarcy.com and then log in to your Scholarcy Library account again.
You may also need to temporarily disable any Adblocker extensions you have running while you carry out this process.