I think the effective answer is you don’t; this is for services. However, sandboxes for this specific purpose exists too: Flatpak, for example. If you want to s

I think the effective answer is you don’t; this is for services. However, sandboxes for this specific purpose exists too: Flatpak, for example. If you want to sandbox programs that are part of the system installation, Firejail can provide pretty useful sandboxing. SELinux and AppArmor also can be configured directly, and some distros will come with default configuration for system apps. No one solution will ever be a panacea for either security or use cases, but together they can help build a setup with defense-in-depth.