https://bugs.kde.org/show_bug.cgi?id=345830
--- Comment #2 from darkli...@gmail.com ---
I've never worked with KDE source code.
Anyway, I've looked into source code of Okular and I noticed that it's not easy
to implement this feature because a backend for a document is 'queried' by
document type.
https://bugs.kde.org/show_bug.cgi?id=345830
Bug ID: 345830
Summary: Option to set backend explicitly
Product: okular
Version: 0.21.1
Platform: unspecified
OS: Linux
Status: UNCONFIRMED
Severity: wishlist
