Since the most recent batch of updates to Leap 42.2 (2 days ago) I’ve been getting TLS failures in KMail including the error “The certificate cannot be verified for internal reasons”
This seems similar to a defect from 2009 which puts the cause as a KDE internal defect, e.g. https://forum.kde.org/viewtopic.php?f=215&t=82617&hilit=The+certificate+cannot+be+verified+for+internal+reasons
Is anyone else seeing this, or am I just lucky?