inkscape tooltips unreadable

Disabling "apply colors to non Qt applications" worked for me.

If you do not want KDE to override your GTK settings, select Colors -> Options in the System Settings and disable the checkbox Apply colors to non-Qt applications

Sources: https://bugs.kde.org/show_bug.cgi?id=355540 https://classicforum.manjaro.org/index.php?topic=29859.0

Before:

After:

For me(on Kubuntu 15.10), it worked by using Oxygen-gtk theme for GTK2 as well as GTK3. Orion and Pearl themes did not work. Now the interface and tool tips, both look native.

Appending the following text to ~/.gtkrc-2.0-kde4 worked for me:

style "gnome-color-chooser-tooltips"
{
bg[NORMAL] = "#FFFFAF"
fg[NORMAL] = "#000000"
}
widget "gtk-tooltip*" style "gnome-color-chooser-tooltips"

I found it in this discussion.