How to remove white border in gVim 8 with gtk 3

Question

I recently updated my gVim to version 8 compiled with gtk 3, and I found there are strange inner borders around the gVim window:

This picture may not very clear but if you look carefully you can see the white borders on the right side and the bottom. I have solved this issue by setting a dark color to the border on gtk 2, but on gtk3 it happends again. Any idea of removing this border completely on gtk 3?

Answer 1

Gtk3 uses css to style applications. To remove the white border from the gVim window, edit the file ~/.config/gtk-3.0/gtk.css and enter the following:

@define-color YOUR_BACKGROUND_COLOR #rrggbb;

window#vim-main-window {
    background-color: @YOUR_BACKGROUND_COLOR;
}

Answer 2

I created a plugin to solve this issue. But it is Windows only: github.com/gabr/FixGVimBorder