Installing from FlatHub

GUI

Discover (KDE Package Manager)

Choose Search and type Discover Overlay. If you don’t currently have Discord get that here too

Gnome Software

Choose Search and type Discover Overlay. If you don’t currently have Discord get that here too

Terminal

Enable Flathub

If your flatpak doesn’t currently have flathub repository added, that’s the first step

flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo

Install Discover Overlay

flatpak install io.github.trigg.discover_overlay

if you don’t currently have Discord you can get that with

flatpak install com.discordapp.Discord