Run a Flathub app using chroot?

Hello, for testing purposes I would like to run an application distributed on Flathub without Bubblewrap.

I was thinking of using mount --bind and chroot, something vaguely along those lines:

mount_point=$(mktemp -d)
mkdir -p ${mount_point}

mount --bind  /var/lib/flatpak/app/some.app/x86_64/latest/active/files  ${mount_point}
mount --bind /var/lib/flatpak/runtime/org.gnome.Platform/x86_64/3.36/active/files \
             ${mount_point}

Questions:

  • Is something like this expected to work?
  • How can I find out what I need to mount, and where? Especially things like the graphics driver runtime and things like that
  • Is there another/better way to run an application from Flathub when you cannot, for some reason, use Bubblewrap?