After an update to 17.08.1 dolphin and konqueror started replacing all non-latin letters in filenames (but NOT in its own interface) with '�'-characters. And it gives out false filenames with these characters to apps on "opening" them, so they can't actually find the file. Changes to LC_* do nothing.

dolphin's log says only:
kf5.kio.core: Refilling KProtocolInfoFactory cache in the hope to find "stash"
Trying to convert empty KLocalizedString to QString.
qt.accessibility.core: Cannot create accessible child interface for object:  PlacesView(0x562c3ebdead0)  index:  32
QLayout: Attempting to add QLayout "" to PhononWidget "", which already has a layout

Like it's not enough that update just before that one broke konqueror's session loading from command line which could have been used with custom desktop-files to compensate for the lack of automatic session save/restore and update of krusader to Qt5 before that one have broken all of its icons for files making their types indistinguishable by eye. Now I'm done to pcmanfm-qt & mc as FMs. And you're not going to fix that like you've done for the last 5 years so I don't know why I'm even writing these anymore. And, apparently, running kate as root is forbidden now by The Computer Gods or something, yeah. Now there is only gwenview/kipi & yakuake/konsole-part left to break and KDE can go straight to a garbage pile in hell.