I did not apply and test this patch yet, but I see that python-kde4 (and so a lot of KDE-related libraries) is needed to make HPLIP's applet using the new application indicator concept. HPLIP's GUI is a pure Qt application and not a KDE application. To improve the probability that upstream accepts it it would be much better to have a Qt-only patch if possible.
I did not apply and test this patch yet, but I see that python-kde4 (and so a lot of KDE-related libraries) is needed to make HPLIP's applet using the new application indicator concept. HPLIP's GUI is a pure Qt application and not a KDE application. To improve the probability that upstream accepts it it would be much better to have a Qt-only patch if possible.