The best place to start if you need help with a specific product is to contact the developer. All WHMCS Marketplace developers have both a website and support URL listed.
Official GoDaddy Wholesale Domain Registrar Module
Favicon manager module lets you add a favicon image to your WHMCS website.
Social Login is a free WHMCS plugin that allows your visitors to comment, login and register with 35+ social networks like for example Twitter, Facebook, LinkedIn, Instagram, Google and Yahoo.
Display social buttons to allow your customer sharing your website products and pages to Facebook, Twitter, Pinterest, LinkedIn, Reddit, etc