What’s the best way to run Firefox in a container?

Both Snap and Flatpak can work as containers for running apps. Snap integrates more with the system yet can be less demanding overall, while Flatpak is super isolated but feels a bit slower when you adjust permissions. Personally, I think the Snap version of Firefox strikes a nice balance without needing much input from the user.

Flatpak is technically not a full container; it sandboxes apps rather than fully isolating them. If you want true containerization, Docker is the way to go. Virtual machines can work too, but they’re more resource-heavy.

You might want to check out Kasm. It's a cool way to run browsers via Apache Guacamole inside Docker, and it's pretty straightforward to set up!

If you're looking for a consumer-friendly option, consider using Podman or Docker with Dropbox to create a lightweight distro and then install Firefox in there. Using Firefox as a Flatpak is also a good approach since it provides sandboxing.