I have bisected the GTK code to find what commit introduced the change in behavior:
commit 99c4f2dd3947c290e3ea19153202be3e43b22add Date: Wed Mar 18 15:22:09 2015 +0100
render: Make image effect not depend on state
Instead rely on -gtk-image-effect only. Adwaita should already work this way.
Relying on state was a leftover feature from the GTK 2 days.
Since this change, it is required to use "-gtk-image-effect: dim;" for insensitive elements. Also, in GTK 3.20+, the attribute was renamed to "-gtk-icon-effect", see https://mail.gnome.org/archives/commits-list/2015-December/msg00151.html
So I suggest to add both gtk-image-effect and gtk-icon-effect to fix the issue in 16.04 (GTK 3.18) and for 16.10 (GTK 3.20?). I will post a patch to achieve that.
I have bisected the GTK code to find what commit introduced the change in behavior:
commit 99c4f2dd3947c29 0e3ea19153202be 3e43b22add
Date: Wed Mar 18 15:22:09 2015 +0100
render: Make image effect not depend on state
Instead rely on -gtk-image-effect only. Adwaita should already work this
way.
Relying on state was a leftover feature from the GTK 2 days.
Since this change, it is required to use "-gtk-image-effect: dim;" for insensitive elements. Also, in GTK 3.20+, the attribute was renamed to "-gtk-icon-effect", see https:/ /mail.gnome. org/archives/ commits- list/2015- December/ msg00151. html
So I suggest to add both gtk-image-effect and gtk-icon-effect to fix the issue in 16.04 (GTK 3.18) and for 16.10 (GTK 3.20?). I will post a patch to achieve that.