Make the Adwaita header bar / title bar dark
It would be great if the Adwaita header bar / title bar could be dark.
The most obvious use case is to reduce eye strain, especially when the app is dark (sublime text, etc...).
There is 2 possibilities. The first one is to make the header bar / title bar dark on the light theme. The second one is to create a "darker" variant with the header bar / title bar dark.
The "darker" variant is the better option but need more work. That said, since the Gnome developers doesn't recommend the use of custom theme, that can be a good solution to lower the need to use third party theme.