GNOME does not come with a system tray. The extension TopIcons Plus used to be the goto for adding a tray back into GNOME. However, the developer has ceased development. GNOME and KDE have both gone to libappindicator instead of the legacy system tray. Quite a few applications now support this, such as Pidgin, Clementine, Discord, Dropbox, Telegram, and potentially many others.
The extension needed is (K)StatusNotifierItem/AppIndicator.
GNOME Developers seem to think minimize/maximize is not a useful feature of a desktop environment. To enable it, run the following as your user:
% gsettings set org.gnome.desktop.wm.preferences button-layout 'appmenu:minimize,maximize,close'
When using Pidgin in GNOME, there’s no default tray for it to live in. You will need to install the (K)StatusNotiferItem/AppIndicator extension from the gnome extension website. And then install this package:
% dnf install pidgin-indicator -y
In pidgin, click tools -> plugins, enable Ubuntu Indicator and restart pidgin.