A key with a comment in the UID is displayed differently in the sign/encrypt dialog depending on whether its in the "Encrypt to me" or the "Encrypt to others" field:
{F18999653}
The comment in the user ID is shown in the "for others" field but not in the others.
This is the same for the corresponding notepad fields.
The comments should be shown in all fields.
We already show the whole UID including the comment in the name field of the certificate list, too.
This ticket relates to T7473 regarding the different tooltips in those cases.