KDE Certification Authority Tool

Current Let's Encrypt certificates use 128 bit serial numbers, providing for more entropy and a larger space to use.

It is possible this is because Let's Encrypt issues new certificates every 90 days and thus is required to have a larger serial number pool while regular CA's usually issue new certificates only once a year if at all and may not require such a larger amount of serial numbers.

More bits in serial numbers do not increase certificate security provided they are sufficiently random when issued.

This would need modification of the underlying database structure as well as all data handling methods as there is no 128 bit unsigned int primitive available, neither in c++ itself not in Qt.