> OK, I managed to get somewhere. Make the manager a static and don't destroy it.
> Then connect and expose and you get this. I'm not sure of the whole approach of having two apps will work, as it's assuming you need two camera objects? I guess it would make more sense to somehow get at the preview buffer for the still app.

Each of those App classes instantiates its own camera and camera manager objects, this is why it keeps crashing. libcamera won't allow either of those classes to have multiple instantiations which is why removing the libcamera-apps dependency is a good idea, possibly necessary.

In other news I put together a little program to extract the parameters available from any attached cameras, here's the output for my HQ camera:

$ LIBCAMERA_LOG_LEVELS=ERROR ./cam_list
Found 1 cameras.1: 'imx477' (/base/soc/i2c0mux/i2c@1/imx477@1a)
    ScalerCropMaximum: (0, 0)/0x0
    ColorFilterArrangement: 0
    PixelArrayActiveAreas: [ (8, 16)/4056x3040 ]
    PixelArraySize: 4056x3040
    Rotation: 180
    Location: 2 
   UnitCellSize: 1550x1550
    Model: imx477