Problem with digital signature

I have an issue. I am trying to enable digital signature in Writer, but I get:

There are problems with at least one signature: the certificate cannot be authenticated.

I have set the folder, where there is certificate from Firefox, which I use for other authentications (e-banking, etc.). Should I do anything extra? Is this certificate not enough for the digital signature?


ps. I use LibreOffice on Fedora 34 with Gnome 40

It might be that the certificate that was used to sign the document can’t be verified due to a missing certificate in the chain, i.e. the root certificate or an intermediary certificate not being present.

Certificates have always been a headache for me… The following comment is to be taken with caution. I leave it to the more experienced people to correct me or to validate my words.

Your certificate is probably self-signed.
For a self-signed certificate, the root certificate authority cannot be verified and this warning message will be displayed.

To my knowledge, there is no root certificate authority that offers a signing certificate for free (or at a reasonable price). Unless you are a company, self-signed certificates are the only way.

You can add your self signed authority certificate to the list of trusted root authorities, and you won’t get that message anymore, but the people you send your document to will see it, unless they also install your certificate authority (which is probably the best option).

Thanks for your input. Actually I have a certificate from the state. In Slovenia everyone can get the certificate for free, because it’s necessary for using anything from the state (e-governance, e-taxes, e-health, etc.) through webbrowser (Firefox, Chrome, etc.).

This may be a lead… be careful, Firefox has its own certificate store (maybe other browsers too…). So a valid certificate in Firefox, will not necessarily be installed on your OS (and so in LO), unless you do an export of the browser and an import in the OS.

Hmm…I was following this guide Applying Digital Signatures

oh… yes, that’s the right way. It’s just me who got confused between Windows and Linux. Sorry false lead😁