Symptoms:
- I’m getting errors every frame about Post Processing, including a message about “Kernel V0Downsample”.
Resolution:
Find the 'Packages/Post Processing/PostProcessing/Shaders` folder, and reimport it (right click > Reimport, on the whole Shaders folder).
After a recompile, these errors should stop, and are then safe to clear.
If you continue to experience this error after taking the advised steps above, please raise a new support request with Unity.