Importing intermediate certificate into Chromium/Cromite

Some websites only serve leaf/server certificate instead of the usual certificate chain (leaf + intermediate). If a browser doesn’t have the corresponding intermediate certificate (that signs the leaf certificate) cached beforehand, this can cause certificate error.

To download the missing intermediate certificate, click on “Not secure” > “Certificate details” > Details tab > “Authority Information Access”, there should be a link next to “CA Issuers”.

The easiest way is to import the downloaded certificate in Chromium/Cromite is to use the built-in Certificate Manager (chrome://certificate-manager/localcerts/usercerts). If you use p11-kit (trust anchor --store interCA.crt) to import, Cromite may not necessarily trust it; in that case, in Certificate Manager (chrome://certificate-manager/localcerts), enable “Use imported local certificates…”.