I'm using Gnome 3 with Ubuntu. I've manually replaced a few low resolution icons in the application menus. However, when switching between programs, some of the icons are still of low quality. Here's a screenshot. Emacs, Terminal and Chrome are fine, MATLAB apps are not, even though the MATLAB launcher is fine.
I'm not sure if this is related to the same problem in Unity. Also, I'm not sure if it's specific to those applications. If there's a way of fixing the icons manually (as I've been doing for the launchers), I'd accept that as an answer.
I've been trawling the Internet to try to resolve this but I really haven't come up with anything. Help appreciated and apologies if it's not Ubuntu-specific and thus off-topic.