GTK3 apps maximize and close buttons not showing the right title bar button theme.

[kdgnlx]

I applied a theme with "whitesur" style title bar button. In GTK4 apps everything works fine but for firefox and any gtk3 app I can only see the color theme but not the themed title bar button. Only the adwaita default ones.

I followed the steps to install Gtk3theme.adw-gtk3 and gave proper permissions to flatpak apps.
https://github.com/lassekongo83/adw-gtk3

[tfuxu]

@kdgnlx
You need to also add custom CSS for titlebar buttons to GTK3 output CSS in Custom CSS textview.