Created by: MartijnCuppens
Fixes #25453 (closed).
The text of dark tables/theads is white and invisible if the page is printed (some browsers don't print backgrounds). Wrapping the theming for dark tables in a @media not print media query will disable theming for dark tables for print.
Also I removed the lines which forced the tds and ths to have a white background. If a table/row/cell has an accented background, you would probably also want this when you print the page (if the browser supports coloured backgrounds).