Expand extensions

Extensions make temporary modifications to the snap’s project file with useful boilerplate, right before the snap is built. They help incorporate known solutions that are common to a supported technology. Run the expand-extensions command from your project’s root directory to see how the project file will look with the extensions applied.

crafter@home:~$

snapcraft expand-extensions

name: foliate
[...]
layout:
  /usr/lib/$SNAPCRAFT_ARCH_TRIPLET/webkit2gtk-4.0:
    bind: $SNAP/gnome-platform/usr/lib/$SNAPCRAFT_ARCH_TRIPLET/webkit2gtk-4.0
  /usr/share/xml/iso-codes:
    bind: $SNAP/gnome-platform/usr/share/xml/iso-codes
apps:
  foliate:
    command: usr/bin/com.github.johnfactotum.Foliate
    plugs:
    - gsettings
    - home
    - desktop
    - desktop-legacy
    - wayland
    - x11
    slots:
    - dbus-daemon
    common-id: com.github.johnfactotum.Foliate.desktop
    desktop: usr/share/applications/com.github.johnfactotum.Foliate.desktop
    command-chain:
    - snap/command-chain/desktop-launch
[...]

See the expand-extensions reference for more details on this command.