Slack is packaged as flatpak on flathub: https://flathub.org/apps.html https://flathub.org/apps.html Various versions of firefox as flatpak are here: https:/

Slack is packaged as flatpak on flathub: https://flathub.org/apps.html https://flathub.org/apps.html Various versions of firefox as flatpak are here: https://firefox-flatpak.mojefedora.cz/ https://firefox-flatpak.mojefedora.cz/ Getting some of those on flathub is a work in progress.