ELA-525-1 was rolled out, fixing CVE-2021-43527 in nss, but that lead to a regression, preventing SSL connections in Chromium. The complete bug report could be found here: https://bugs.debian.org/1001219.
For Debian 8 jessie, these problems have been fixed in version 2:3.26-1+debu8u15.
We recommend that you upgrade your nss packages.
Further information about Extended LTS security advisories can be found at: https://deb.freexian.com/extended-lts/