Can I use the private SSL for the primary domain with an addon domain?
The recent SNI technology allows multiple SSL certificates to be installed on one IP address, therefore it is possible that an account has more than one private SSL certificate associated to it.
As of December 2016, you can use separate and different private SSLs for your primary domain and for your addon domains under the same SiteGround account. For example, you can have a Let's Encrypt and a Wildcard SSL certificates installed on different domains or addon domains under the same account.
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