Created attachment 144101 [details] messages from Adobe Reader I have recently checked that Poppler can provide both: 1. signed PDF content verification (i.e. content was not changed after signature) 2. identify verification, given trusted CA certificates (inserted into the Firefox NSS cert db) Reference: https://gitlab.freedesktop.org/poppler/poppler/-/issues/896#note_1172603 It seems to me that oKular when it says "the signature is cryptographically valid" it refers to 1), which might not be 100% clear to whoever sees that message. Ideally oKular would be able to perform 1 and 2, like Poppler does, and display different messages depending on whether both checks are performed or only the first so that the users understands the level of validation. I am attaching the messages from Adobe Reader to illustrate the idea.
Created attachment 144102 [details] another message panel from Adobe Reader
A possibly relevant merge request was started @ https://invent.kde.org/graphics/okular/-/merge_requests/917