If you have implemented or planing to implement the “URL Preview” feature for HCL Connections, make sure you import the Root Certificate for “Let’s Encrypt” certificate authority inside the java trust store.
By default, the root certificate of “Let’s Encrypt” certificate authority is not in the java trust store which the HCL Connections documentation suggests to use for URL Preview. Which means that if you do not import it manually, the URL preview won’t work for websites which are using “Let’s Encrypt” certificates.
Thoughts about HCL Connections, Domino and Sametime 