Currently Okular does not support XFA Forums. I'd like to improve this as not being able to edit XFA forums is incredibly frustrating especially when filling out government documents. I'd like to know what the best method to add this to Okular as it is really the only annoying thing i need an adobe product for.

create an account and vote for the wishlist/bug on bugs.kde.org https://bugs.kde.org/show_bug.cgi?id=263042

maybe with enough interest it will be included in the GSOC proposal https://community.kde.org/GSoC/2015/Ideas#Okular

of course this feature would need to be in Poppler (the rendering backend, it is not a KDE project) for Okular to be able to add the functionality and no idea if it is