We honor dark mode when showing drawings in the UI. We can do this because Apple’s frameworks alter the colors to match. If you drew in light mode with black, it will be white when you switch to dark mode.
This doesn’t work for exports though, of course. Other apps can’t do this trick, so if you print or export, you always get the light mode look. That’s why we show that in the preview. It’s the image as it would be exported (which is even possible from the preview sheet).
Yes, the preview is of an image that you would get if you exported, emailed, printed etc. It is a standard document presentation sheet of apple, so we have to provide a standard document there.
Personally, I’m ok with the preview image being white. But I would much prefer that the background be black (as opposed to dark gray) when displayed inline because the image has a black background when I’m drawing in dark mode.
Do you have the ability to change the background on the inline image? Or is that coming from Apple too?
EDIT: Or rather, ideally not a black background, but a background that matches the dark theme background.
You’ll be happy to know we have changed this so that transparent images are now really transparent. No white background, except for PDFs, which are nearly always designed to be on white.