I want to run a shell script that might open my browser to a specific website. I don't want the page to load when this happen. But I cannot switch off my internet access also (as I use the internet to remotely access another system at the same time). So I am planning to isolate the run time environment for the shell script.

I an on Arch and I used to use a AUR package called bubblejail to do this. But with the whole AUR security fiasco, I am not trusting any packages from AUR. I can switch to another distro if needed, like Rocky or something.

So my requirement is, Internet sandboxing for a terminal and the processes it spawns. Preferably using flatpak commands.

Edit: I tried disabling the internet usage for a terminal from Flathub using Flatseal. Sure I cannot curl after this, but when I launch my browser using it, it had Internet access.