Could other code signing systems like macOS gatekeeper also be vulnerable to problems like this? IMO this seems like just plain bad design. The Firefox addon c

Could other code signing systems like macOS gatekeeper also be vulnerable to problems like this? IMO this seems like just plain bad design. The Firefox addon certificate should never have had an expiry date. If they ever needed to revoke it, they could distribute an updated version of the browser with the previous intermediate explicitly marked as revoked.