Hi, maybe hot corners (actions and animations happening when you move mouse cursor to screen corners) are to heavy for your computer, especially when FireFox probably consumes most of the remaining RAM.
I don't know what's your GPU (it might be the reason of the slowdown), but with 2GB of RAM, experience on Gnome (default Fedora Workstation desktop environment) might be subpar anyway. Here are Fedora spins (with different desktop environments; also those images already have most of latest updates incorporated), you can test them e.g. by booting them from a live USB: https://dl.fedoraproject.org/pub/alt/...
LXDE (and LXQT) will be the lightest on resources, while Xfce, especially with Whisker menu (xfce4-whiskermenu-plugin) added, will be more convenient (e.g. search field in application menu) and only slightly heavier.
You can also add other desktop environments to your current system by following this instruction: https://docs.fedoraproject.org/en-US/...
P.S. With prices on used RAM not being to high, you could quite cheaply upgrade it, just make sure it will be compatible with your motherboard.
