I'm currently using the Adapta-Nokto theme on Linux Mint 18.2 Cinnamon. When using any dark theme (specifically the Controls portion of it), some web inputs (presumably those with some form of background-color attribute missing) default to the background color used by input fields in the system. This would be fine, if not for them still retaining the black text color. This makes things very difficult to see when doing any form of input. See below (the Dropbox search bar):
Is there even a fix for this? I've noticed it when I first installed Mint and used one of the default dark themes too, so as I mentioned this is apparent for any dark theme.