I have always used the dark forum theme, so I never noticed this before, but I think it is a design mistake?:
When previewing a new post using the light theme, the preview renders the text in a very light grey, making it difficult to read.
And since the actual post will have the text in black, it's probably a mistake/oversight?
And I now also suddenly understand why sometimes a poster will manually set the text of his post to black (rendering it unreadable for users of the dark theme).
In hindsight I now forgive those that I may have cursed for doing that ;-)
Or is it perhaps something off with my system? It seems weird that nobody ever noticed or reported this?