#524 Change color of warnings in Console

Closes #524 (closed)

Dark mode: Contrast ratio 8.26 : 1

Light mode: Contrast ratio 4.01 : 1 (Same as the red color we use, but maybe we want more contrast, it does not pass the WCAG AA test, which requires 4.5)

Let me know what you think. If we don't like a separate warning stream, that is also fine.