Allows to customize the date format on the panel.
You can use dconf Editor to change format. Or simply from the terminal:
dconf write /org/gnome/shell/extensions/panel-date-format/format "'%Y-%m-%d'"The format strings understood by this function are a subset of the strftime(). The following format specifiers are supported.
This repository for developers only. If you wanna add this extension to your desktop, get it from extensions.gnome.org.