We could reproduce this issue at our end, following are the findings
1. This issue is reproducible in CPU, GPU Rendering and Print Preview(thumbnail).
2. Reproducible in older versions as well including Illustrator CS6 (not a new break in CC 2018)
3. Works fine in Overprint Preview
4. Works fine in Print & PDF
Please confirm above observation match with the problem reported in this issue
An error occurred while saving the commentDan commented
-Blending modes not working- Turning to black
Blending modes are not working properly. I've notice that mostly AMD's users having this issue. To my understanding it is because AMD is working properly with the latest CC 2018 update. If someone has a solution to this please help.