Additional auto mark function: mark only files visible on current screen

[Gridwolf]

Sometimes I have to be very careful with sorting duplicates since I don't want to delete duplicates in an album.
It would really come handy if I could mark the files with the auto mark settings, but only on the current screen (so that I don't have to scroll) and with the normal marking mechanism (like when I use Ctrl + Left Mouse Button).

[Admin]

Hm, it's very uncomfortably to resize window to set correct visual selection, maybe better automark only selected files ?

[Gridwolf]

Working with the selected files is a valid option, true.

I didn't mean to resize the window. I would get the current height of the list control divided by the line height (which you also should know), thus knowing how many lines are displayed at the moment.
The only tricky thing I can imagine is finding out which is the first line currently displayed...