Old root certificate of Let's Encrypt TLS certificates for custom domains has expired

Thank you for looking into this! Electron applications also can’t communicate with Netlify currently, unless they’re built from a version of Electron that was released yesterday. Removing the expired certificate from the chain should fix that for Electron too. That would make my life a lot easier, as for now I’ve had to move some files off of Netlify, which is obviously much less convenient.