This site used to always use SSL certificates from Symantec, but after all, it was a free DV certificate. After the root certificate for WoSign’s (WoSign) widely issued free DV certificates was revoked last time, I couldn’t help but worry that Symantec might one day face the same punishment.
Moreover, according to official news from Google, Google will gradually reduce its trust in Symantec SSL. So I decided to switch to a more trusted certificate authority, and chose the long-established provider Comodo (Comodo).
As it happened, Namecheap launched a Symantec certificate replacement program a few months ago, allowing Symantec SSL certificates to be replaced with Comodo SSL for free. The new certificate (Comodo SSL) has the same expiration date as the original certificate (Symantec SSL). Once it expires, you can choose whether to renew it.

New Certificate
Here is a screenshot of the Comodo SSL certificate I just switched to:

There is also a screenshot of the Comodo SSL root certificate:
