Allow to create citations entries by manually specifying data in <cite>?

[krassowski]

I originally designed the extension to handle manually inserted citations using data attributes of <cite>, but this had to postponed until later due to more urgent issues. It might be nice to allow to cite things manually (though making an entry in the reference manager for that citation should be preferred - if possible).

[jmakov]

When I add a text, it gets deleted after 2s... Adding entries locally should be preferred IMO. Also what's the recommended workflow if multiple users contribute to the notebook - should we have a separate Zotero account for every notebook?