Created attachment 138709 [details]
This never seems to work in versions before 6.0 RC1 and it still doesn't work.
Take a look at the screenshot submitted: it has an expired certificate that seems to come with LO. Then, it has my key whose expire date is 00-00-0000 (it should show "Never" instead of that).
Then, signing a document that only has the text "123" spends hours with the mouse pointer busy and never ends.
I believe I tried to sign a PDF with 6.0 RC1 and it doesn't work.
Before I forget: LO says there is no "Certificate Manager blah blah" when I have installed Gpg4win 3.0.2 which has Kleopatra.
As for expired certificate, I wrote in Bug 113190. You may follow.
As for expire date is 00-00-0000, there's no reason to put never to this field type so it's WontFix.
As for "signing a document that only has the text "123" spends hours" no repro. If you want this to be in this bug, you need to write reproducible steps. Since we cannot request certificates like we request documents, it would be helpful that you test with master http://dev-builds.libreoffice.org/daily/master/ as I requested. Also screencast of what you do or attach a zipped series of screenshots. And write which exactly is certificate you use. If you still repro that with master, please set back to Unconfirmed.
As for Comment 1, I reported as Bug 116085. You may follow.
Whole report is Invalid because it mixes different issues.