Friday, January 11, 2019

Okular: PDF Signature + Certificate support has landed

As of a few minutes ago, i merged the code from Chinmoy Ranjan Pradhan's GSOC to support showing PDF Signatures and Certificates in Okular.

Signature handling is a big step for us, but it's also very complex, so i expect it to have bugs and things that can be improved so testers more than welcome.

Compiling is a bit "hard" since it requires poppler 0.73 that was released a few days ago.

But thanks to flatpak, there's no need to compile it, you can run the KDE Okular Nightly on your system to try it

flatpak remote-add --if-not-exists flathub
flatpak remote-add --if-not-exists kdeapps --from
flatpak install kdeapps org.kde.okular

Note: if you have okular installed from another flatpak repo (for example flathub) this will switch you to the KDE Nightlies, you may want to switch back after testing.

And then you can try the adobe sample pdf
flatpak run --share=network org.kde.okular

And you should get stuff like this


Anonymous said...

Oh! Does this mean you have the ability of Adobe Sign and Fill?
Can I sign documents with a wacom tablet?
When will it be rolled into the stable Okular?

Albert Astals Cid said...

You can not create new Signatures, just verify the existing ones.

This will be rolled into stable with KDE Applications 19.04 (unless something catastrophic is found)

Anonymous said...

ok. Thanks

parapente said...

Very nice indeed! It was a feature that I was looking for for a long time. After running a few tests I can say that it seems to work well. A couple of wishes:
* A way to indicate upon opening a file there is a problem with the signature (like the green, red notifications that appear in adobe reader)
* Some pdf files change the annotation when the signature is checked. One such file can be found here (

Albert Astals Cid said...

@parapente please file bugs in with those wishes otherwise they'll be lost in here.