Develop image not showing correctly, making editing impossible

[mijbil250456]

I've got a new bug with Lightroom which is intensely irritating, and is making editing impossible. The Develop window does not show the image correctly with adjustments applied, the only correct version is in my secondary window. The screenshot below shows the problem clearly. The highlighted images is BW in the secondary window grid display, and the adjustment sliders on the right confirm this, however the image I am trying to edit is in colour, with some, but not all adjustments applied (it is cropped, and some tonal adjustments seem to be applied).

This is the same for all images - if I apply a preset, the adjustment sliders move, and the secondary image shows correctly, but the navigator and develop windows don't show the changes.

I have tried the usual restart, and also updating to the latest version of LR CC, no change.

Any ideas?

[sharp_hands16B8]

This appears to be a preview issue. Smart Preview has been buggy for some in the past. Maybe start there and see if toggling any settings changes anything for you.
How to use Smart Previews to view and edit photos in Photoshop Lightroom Classic CC

[TheDigitalDog]

Could be a corrupted display profile. Can you recalibrate and build a new profile for both displays? Make sure you do not ask for a version 4 (V4) spec profile and if the software allows you to pick between LUT and Matrix, pick Matrix. Any difference?

See: I can only see changes to the upper left Preview Picture Lightroom Classic