It would be great if the Facebook messages collection would actually be a mail collection, so that the messages would show up in KMail and I could easily browse, search and read them. Next step would be to allow the user to reply to them from right there. Reproducible: Always
Interesting idea. I think it could be done; it would require extending KFbAPI (the facebook lib) and then the resource. Should be easy, even :) I'm happy to review those patches and maybe get it to kf5-based resource too, but I have no plans on working on the kdelibs4 versions.
*** Bug 203530 has been marked as a duplicate of this bug. ***
Unfortunately Facebook no longer provides access to messages through any of their APIs.