Nothing Happening / Sandbox root error

[Blackfire-dev]

Just wanted to know if you can add this to the installation section of your guide. As a newbie to Linux myself, I eventually figured it out but it might be useful for those less experienced.

Once extracted to a folder of your choice, to open Stellar, double click the file "stellar-mod-loader"

If nothing happens, it is possible you need to set file permissions for the sandbox. To do this open your console and navigate to the folder where you extracted Stellar and run these two commands.

sudo chown root:root chrome-sandbox
sudo chmod 4755 chrome-sandbox

You should now be able to double click "stellar-mod-loader"

[lVlyke]

It looks like this is related to changes made to the default AppArmor configuration starting with Ubuntu 24.04, as described in this Ubuntu blog post. The recommended approach is to create an AppArmor profile for the application to allow it to use unprivileged user namespaces, which is required for Electron apps that use sandboxing (see electron/electron#42510 for more info).

Since Stellar is currently only distributed as a portable application (i.e. not installed through a package manager), this unfortunately makes it impossible to install an AppArmor profile automatically. It should, however, be possible to create a shell script that can generate the required AppArmor profile for users on Ubuntu-based systems. I will add this as part of the next release.

In the meantime, Ubuntu users can manually create an AppArmor profile for Stellar at /etc/apparmor.d/stellar-mod-loader with the following contents (replace <path-to-stellar> with your installation location):

abi <abi/4.0>,
include <tunables/global>
<path-to-stellar>/stellar-mod-loader flags=(default_allow) {
  userns,
  include if exists <local/stellar-mod-loader>
}

Finally, make sure to reload AppArmor with systemctl reload apparmor.service. Stellar should now be able to run.