It is possible, and you found the right link. Just restart the gnome shell after changing the values. Weird thing is though, the values change back after a restart. If you find out how to fix THAT, let me know
Well, I've just found out it is actually working for me too, apparently I made some typo in my previous attempt. I've just followed advices from that link I posted and changes persist after reboot too.
Here is modified part of /usr/share/gnome-shell/theme/gnome-shell.css:
#message-tray {
background: #2e3436 url(message-tray-background.png);
background-position: 0 0;
background-repeat: repeat;
transition-duration: 250;
height: 36px;
Note that only thing added here to original gnome-shell.css are these 2 lines:
background-position: 0 0;
height: 36px;
Additionally, to make notification icons fit into this now tiny notification bar, I put this value in /usr/share/gnome-shell/js/ui/messageTray.js:
SOURCE_ICON_SIZE: 18,
I have no clue why your changes are not persistent, it might take a little investigation at yours side, but I can confirm that this hack is working.
]]>Modifying /usr/share/gnome-shell/theme/gnome-shell.css didn't work for me, I've only managed to change the icons' size in /usr/share/gnome-shell/js/ui/messageTray.js.
Anyone done it yet or have an idea?
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