Keep in mind that the "Certificate Details" can also be shown for search results in the server lookup. In this case not all properties are available, e.g. there is no information about certifications, so that it might not make sense to show the certifications tab. Or we show the tab (so that the users don't wonder why it's missing), but display a message explaining that this information is not available before the certificate is imported.

Optimization requests:

In details window:

• add regular padding around the buttons in the tabs

Tab "Certifications":

• Show Fingerprint instead of Key-ID of certifications (change the title correspondingly)

[edit: some bullet points moved to subtasks T7094, T7095, T7096]

I don't like blowing up a task with loads of unrelated additional wishes after the original request was fulfilled. At most the first request can be considered part of the original request. The other requests should be handled in multiple separate tasks.

Show Fingerprint instead of Key-ID of certifications (change the title correspondingly)

This makes no sense. A signature carries the (8-octet) key ID of the issuer. Optionally, the Signer's User ID might be attached to the signature. I don't see any mention of the issuer fingerprint in the published RFC for v4 signatures. Hence, for unknown keys it's impossible to show the fingerprint. And for known keys it would, in my opinion, give a false sense of security because we have to use the key ID to determine the key's fingerprint.

We include the ISSUER_FPR subpacket since version 2.1.16 released 2016. Thus there is virtually always a fingerprint for all signatures available.