Bonus points if you fix KSM to actually use the proper current fb orientations on (at least) Mk. 7 devices, because that's currently not the case

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(That part is accurate in FBInk, because KOReader relies on it, c.f., utils/fbdepth.c, with extensive comments about the exact behavior on the devices I own, scattered around set_kobo_quirks() in fbink_device_id.c and initialize_fbink() in fbink.c, with a bit of extra posssibly-not-entirely-accurate fun thrown in around rotate_touch_coordinates()).
If that's actually a viable approach with Sergey's Qt4 plugins, of course. Because they may assume and expect the broken behavior, but I wouldn't know about that

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