Somewhere dxo decided that having access to every last pixel was more important.
What happened is that there always was an option enabled that fixed the black borders when applying distortion correction . Even when ‘only optical and denoise’ is selected in the dng export.
Somewhere in the kast upgrades , that checkbox is now set to DISABLED when you apply the ‘corrections only’ preset.
So, when you pick ‘optical and denoise only’ for dng export , crop is AND WAS never applied .
But distortion correction IS, you just need to enable the checkbox in distortion module that says 'constrain to image ’ to get the old behaviour back
So far as I can tell, there is no bug, just default behaviour that changed with a minor upgrade (which can be just as annoying (.