Created attachment 117846 [details] Selected some text with dark Text Selection Background color As described in bug 384267, I suggest to make the Selection Background color of the Text Selection Tool user configurable, and use the system default color only as default. The problem is that one can use a dark Selection Background color in the system color scheme, but PDFs also have dark text color. This makes it very hard to check what was selected. (See attachment) Kate does it fine, because it not only uses Selection Background, but also Selection Text, View Background, and View Text. So, another option would be to also use Selection Text, instead of just tinting (?) the selection. This way, one could make invisible text visible just by selecting it. (Try that by creating a PDF with some white text on white background, e. g. with Inkscape; then activate Configure -> Accessibility -> Change Colors: Change Paper Color)
Rather than being configurable, maybe it should do something like invert the text color in these circumstances.
I would be happy with simple inversion. I don't recall exactly, but evince does something like this. It wouldn't be that bad if Plasma worked well with a light selection color (global color scheme) but it isn't if you use a light color scheme (because certain elements, e.g. the timeout indicator for notifications, becomes impossible to see).