Electron kiosk app without devmode

Hi,

I have a working electron app.

To run int I need to use devmode

sudo snap install pam-app --channel=latest/edge --devmod

Without devmod, this kiosk app will not start. Is there way to remove the need for devmode?

Here are the errors

Sep 29 15:29:08 SydneyDemo2 pam-app.pam-app[2928216]: ##################################################################################
Sep 29 15:29:08 SydneyDemo2 pam-app.pam-app[2928216]: If you are experiencing problems with your GUI app (e.g. bad fonts), please run:
Sep 29 15:29:08 SydneyDemo2 pam-app.pam-app[2928216]:   snap connect pam-app:x11-plug pam-app:x11
Sep 29 15:29:08 SydneyDemo2 pam-app.pam-app[2928216]: ##################################################################################
Sep 29 15:29:08 SydneyDemo2 pam-app.pam-app[2928395]: _XSERVTransSocketCreateListener: failed to bind listener
Sep 29 15:29:08 SydneyDemo2 pam-app.pam-app[2928395]: _XSERVTransSocketUNIXCreateListener: ...SocketCreateListener() failed
Sep 29 15:29:08 SydneyDemo2 pam-app.pam-app[2928395]: _XSERVTransMakeAllCOTSServerListeners: failed to create listener for local
Sep 29 15:29:08 SydneyDemo2 pam-app.pam-app[2928395]: glamor: EGL version 1.4:
Sep 29 15:29:08 SydneyDemo2 pam-app.pam-app[2928395]: WARNING: Kernel has no file descriptor comparison support: Operation not permitted
name: pam-app
version: VERSION
summary: Digital signage app
description: Digital signage app
base: core18
confinement: strict
grade: devel
compression: lzo

apps:
  pam-app:
    daemon: simple
    stop-timeout: 1m
    extensions: [gnome-3-28]
    restart-condition: always
    command: snap/command-chain/desktop-launch xwayland-kiosk-launch $SNAP/pam/PAMApp --no-sandbox
    plugs:
      - network
      - network-bind
      - opengl
      - pulseaudio
      - wayland

layout:
  /usr/share/fonts:
    bind: $SNAP/usr/share/fonts

environment:
  XWAYLAND_FULLSCREEN_WINDOW_HINT: window_role="browser-window"

parts:
  pam-app-source:
    plugin: nil
    source: out
    override-build: |
      mkdir -p $SNAPCRAFT_PART_INSTALL/pam
      cp -R PAMApp-linux-x64/* $SNAPCRAFT_PART_INSTALL/pam
    stage-packages:
      - libnspr4
      - libasound2
      - libgconf-2-4
      - libnss3
      - libx11-xcb1
      - libxss1
      - libxtst6
    build-snaps:
      - node/14/stable

  xwayland-kiosk-helper:
    plugin: cmake
    source: https://github.com/MirServer/xwayland-kiosk-helper.git
    build-packages: [build-essential]
    stage-packages: [xwayland, i3, libegl1-mesa, libgl1-mesa-glx]

try using the mir-kiosk-x11 build-snap and probably also bump to core20 and the gnome-3-38 extension … i have an example snap using these two here:

I will try it this week.

1 Like

if you hit issues, don’t hesitate to ask :slight_smile:

Hi, I got some problems

name: pam-app
version: "1"
summary: Digital signage app
description: |
  Digital signage app backed by AWS IoT Core
  to be used on Ubuntu Core 20 systems with the ubuntu-frame display
  server.

  First install ubuntu-frame with
    snap install ubuntu-frame

  To change screen orienation 

    snap set ubuntu-frame display="
      layouts:
        default:
          cards:
          - card-id: 0
            DisplayPort-1:
              orientation: left
    "
base: core20
confinement: strict
grade: devel
compression: lzo

apps:
  pam-app:
    daemon: simple
    stop-timeout: 1m
    extensions: [gnome-3-38]
    restart-condition: always
    command: usr/local/bin/x11_kiosk_launch $SNAP/snap/command-chain/desktop-launch $SNAP/pam/PAMApp --no-sandbox
    plugs:
      - audio-playback
      - browser-support
      - hardware-observe
      - network
      - network-bind
      - network-observe
      - opengl
      - process-control
      - wayland

# Needed by Mir and/or Xwayland
layout:
  /usr/share/X11:
    bind: $SNAP/usr/share/X11
  /usr/bin/xkbcomp:
    symlink: $SNAP/usr/bin/xkbcomp
  /usr/share/icons:
    bind: $SNAP/gnome-platform/usr/share/icons
  /usr/share/fonts:
    bind: $SNAP/gnome-platform/usr/share/fonts
  /usr/local/share/fonts:
    bind: $SNAP/usr/local/share/fonts
  /etc/fonts:
    bind: $SNAP/gnome-platform/etc/fonts

environment:
  XWAYLAND_FULLSCREEN_WINDOW_HINT: window_role="browser-window"

parts:
  pam-app-source:
    plugin: nil
    source: out
    override-build: |
      mkdir -p $SNAPCRAFT_PART_INSTALL/pam
      cp -R PAMApp-linux-x64/* $SNAPCRAFT_PART_INSTALL/pam
    stage-packages:
      - libnspr4
      - libasound2
      - libgconf-2-4
      - libnss3
      - libx11-xcb1
      - libxss1
      - libxtst6
    build-snaps:
      - node/14/stable
    stage-snaps:
      - mir-kiosk-x11

errors

Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: [2021-10-20 17:04:11.009005] <information> mirserver: Starting
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: [2021-10-20 17:04:11.011602] < - debug - > mirserver: Not using logind for session management: Failed to find active session
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: [2021-10-20 17:04:11.011710] < - debug - > mirserver: Not using Linux VT subsystem for session management: Failed to find the current VT
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: [2021-10-20 17:04:11.011737] < - debug - > mirserver: No session management supported
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: [2021-10-20 17:04:11.011771] <information> VT switch key handler: No VT switching support available: MinimalConsoleServices does not support VT switching
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: [2021-10-20 17:04:11.011839] <information> mircommon: Loading modules from: /usr/lib/x86_64-linux-gnu/mir/server-platform
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: [2021-10-20 17:04:11.011867] < - ERROR - > mircommon: Failed to load libraries from path: /usr/lib/x86_64-linux-gnu/mir/server-platform (error was:/usr/lib/x86_64-linux-gnu/mir/server-platform: No such file or directory)
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: ERROR: /build/mir-mreCGI/mir-2.5.0/src/server/graphics/default_configuration.cpp(231): Throw in function virtual const std::vector<std::shared_ptr<mir::graphics::DisplayPlatform> >& mir::DefaultServerConfiguration::the_display_platforms()
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: Dynamic exception type: boost::wrapexcept<std::runtime_error>
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: std::exception::what: Exception while creating graphics platform
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: ERROR: Dynamic exception type: std::system_error
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73542]: std::exception::what: /usr/lib/x86_64-linux-gnu/mir/server-platform: No such file or directory
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73543]: /tmp/tmp.ZYP55KYFjD CLOSE_WRITE,CLOSE
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73640]: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libgtk-3-0/gtk-query-immodules-3.0: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73551]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73551]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73652]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73652]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73653]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73653]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73551]: Failed to generate minidump.
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73436]: Segmentation fault
Oct 20 17:04:11 SydneyDemo2 pam-app.pam-app[73436]: /snap/pam-app/x1/usr/local/bin/x11_kiosk_launch: 20: kill: No such process
Oct 20 17:04:11 SydneyDemo2 systemd[1]: snap.pam-app.pam-app.service: Main process exited, code=exited, status=1/FAILURE
Oct 20 17:04:11 SydneyDemo2 systemd[1]: snap.pam-app.pam-app.service: Failed with result 'exit-code'.
Oct 20 17:04:11 SydneyDemo2 systemd[1]: snap.pam-app.pam-app.service: Scheduled restart job, restart counter is at 6.

ubuntu-frame is running

I have removed mir-kiosk

anything I missed?

yup … the env-setup command-chain script …

i also think

can be dropped …

i’m also not sure why you see the libffi errors, is your gnome-3-38-2004 install outdated by chance ?

Oops. I forgot to add

    command-chain:
      - env-setup

Now the snap worked.

But I still get libfii.so errors

Oct 20 20:47:18 SydneyDemo2 pam-app.pam-app[9430]: /tmp/tmp.q7J28YR4Xr CLOSE_WRITE,CLOSE
Oct 20 20:47:18 SydneyDemo2 pam-app.pam-app[9558]: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libgtk-3-0/gtk-query-immodules-3.0: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 20:47:18 SydneyDemo2 pam-app.pam-app[9465]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 20:47:18 SydneyDemo2 pam-app.pam-app[9465]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 20 20:47:18 SydneyDemo2 pam-app.pam-app[9604]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 20:47:18 SydneyDemo2 pam-app.pam-app[9604]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 20 20:47:18 SydneyDemo2 pam-app.pam-app[9605]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 20:47:18 SydneyDemo2 pam-app.pam-app[9605]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9429]: [2021-10-20 20:47:19.407344] <information> xwayland: Starting XWayland
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9627]: /snap/pam-app/x1/usr/bin/Xwayland: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9627]: /snap/pam-app/x1/usr/bin/Xwayland: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9627]: WARNING: Kernel has no file descriptor comparison support: Operation not permitted
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9429]: [2021-10-20 20:47:19.484916] <information> xwayland: XWayland is running
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9656]: The XKEYBOARD keymap compiler (xkbcomp) reports:
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9656]: > Warning:          Unsupported maximum keycode 569, clipping.
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9656]: >                   X11 cannot support keycodes above 255.
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9656]: > Internal error:   Could not resolve keysym Invalid
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9656]: Errors from xkbcomp are not fatal to the X server
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9465]: DEBUG [07:47:19 PM 20-10-2021]: [app-node] Version: 1.0.5, Build: 9b9f403
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9465]:     details: []
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9678]: /proc/self/exe: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9678]: /proc/self/exe: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9429]: [2021-10-20 20:47:19.639072] < - ERROR - > xwayland: XCB error: no reply data
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9429]: [2021-10-20 20:47:19.641044] < - ERROR - > xwayland: XCB error: no reply data
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9429]: [2021-10-20 20:47:19.641099] < - ERROR - > xwayland: XCB error: no reply data
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9465]: DEBUG [07:47:19 PM 20-10-2021]: [app-node] App path: /snap/pam-app/x1/pam/resources/app
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9465]:     details: []
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9465]: DEBUG [07:47:19 PM 20-10-2021]: [app-node] App data path: /root/snap/pam-app/x1/.config/PAMApp
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9465]:     details: []
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9686]: /proc/self/exe: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 20:47:19 SydneyDemo2 pam-app.pam-app[9686]: /proc/self/exe: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)

Do I need to install gnome-3-38-2004 on the host does the build ?

I did clean snap

snapcraft clean snapcraft

Now the snap build will not run

Oct 20 21:08:19 SydneyDemo2 pam-app.pam-app[18609]: /snap/pam-app/x1/pam/PAMApp: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18489]: [2021-10-20 21:08:20.343739] <information> xwayland: Starting XWayland
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18629]: /snap/pam-app/x1/usr/bin/Xwayland: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18629]: /snap/pam-app/x1/usr/bin/Xwayland: /snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/pam-app/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18629]: WARNING: Kernel has no file descriptor comparison support: Operation not permitted
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18489]: [2021-10-20 21:08:20.405139] <information> xwayland: XWayland is running
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18658]: The XKEYBOARD keymap compiler (xkbcomp) reports:
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18658]: > Warning:          Unsupported maximum keycode 569, clipping.
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18658]: >                   X11 cannot support keycodes above 255.
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18658]: Errors from xkbcomp are not fatal to the X server
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18508]: Failed to generate minidump.
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18370]: Illegal instruction
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18489]: [2021-10-20 21:08:20.511249] < - debug - > mirserver: Handling Terminated from pid=18370
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18489]: [2021-10-20 21:08:20.511789] <information> xwayland: Deiniting xwayland server
Oct 20 21:08:20 SydneyDemo2 pam-app.pam-app[18489]: [2021-10-20 21:08:20.612164] <information> xwayland: XWayland stopped
Oct 20 21:08:20 SydneyDemo2 systemd[1]: snap.pam-app.pam-app.service: Succeeded.
Oct 20 21:08:20 SydneyDemo2 systemd[1]: snap.pam-app.pam-app.service: Scheduled restart job, restart counter is at 5.
Oct 20 21:08:20 SydneyDemo2 systemd[1]: Stopped Service for snap application pam-app.pam-app.
snapd 2.52 from Canonicalâś“ installed
"snapd" switched to the "latest/stable" channel

core20 20210928 from Canonicalâś“ installed
"core20" switched to the "latest/stable" channel

core18 20210722 from Canonicalâś“ installed
"core18" switched to the "latest/stable" channel

snapcraft 5.0 from Canonicalâś“ installed
"snapcraft" switched to the "latest/stable" channel

snapd is not logged in, snap install commands will use sudo                     
snap "core20" has no updates available
snapd is not logged in, snap install commands will use sudo
gnome-3-38-2004-sdk 0+git.f8ffa69 from Canonicalâś“ installed
snapd is not logged in, snap install commands will use sudo
gnome-3-38-2004 0+git.6ba6040 from Canonicalâś“ installed
snapd is not logged in, snap install commands will use sudo
gtk-common-themes 0.1-59-g7bca6ae from Canonicalâś“ installed
Pulling gnome-3-38-extension 

gnome-3-38-2004 is installed

/snap/pam-app/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7

this file is not at this path.

are you sure the binary has the correct architecture ?

Yes. The correct architecture.

Same error.

snap run --shell electron-kiosk-uc20
/snap/electron-kiosk-uc20/x2/gnome-platform/usr/lib/x86_64-linux-gnu/libgtk-3-0/gtk-query-immodules-3.0: /snap/electron-kiosk-uc20/x2/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x2/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)

ls /snap/electron-kiosk-uc20/current/gnome-platform

is empty

you rather want

snap run --shell electron-kiosk-uc20.electron-kiosk-uc20

so it processes the command-chain bits …

electron-kiosk-uc20 have does render the page but they have similar errors as my app

Do I need to add interface connections?

Oct 21 09:01:07 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[142998]: /tmp/tmp.DunR1BHlj6 CLOSE_WRITE,CLOSE
Oct 21 09:01:07 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143106]: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libgtk-3-0/gtk-query-immodules-3.0: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 21 09:01:07 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143015]: /snap/electron-kiosk-uc20/x1/electron-helloworld/electron-quick-start: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 21 09:01:07 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143015]: /snap/electron-kiosk-uc20/x1/electron-helloworld/electron-quick-start: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 21 09:01:07 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143120]: /snap/electron-kiosk-uc20/x1/electron-helloworld/electron-quick-start: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 21 09:01:07 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143120]: /snap/electron-kiosk-uc20/x1/electron-helloworld/electron-quick-start: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 21 09:01:07 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143121]: /snap/electron-kiosk-uc20/x1/electron-helloworld/electron-quick-start: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 21 09:01:07 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143121]: /snap/electron-kiosk-uc20/x1/electron-helloworld/electron-quick-start: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 21 09:01:07 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[142997]: [2021-10-21 09:01:07.977700] <information> xwayland: Starting XWayland
Oct 21 09:01:07 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143133]: /snap/electron-kiosk-uc20/x1/usr/bin/Xwayland: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 21 09:01:07 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143133]: /snap/electron-kiosk-uc20/x1/usr/bin/Xwayland: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143133]: WARNING: Kernel has no file descriptor comparison support: Operation not permitted
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[142997]: [2021-10-21 09:01:08.037671] <information> xwayland: XWayland is running
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143162]: The XKEYBOARD keymap compiler (xkbcomp) reports:
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143162]: > Warning:          Unsupported maximum keycode 569, clipping.
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143162]: >                   X11 cannot support keycodes above 255.
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143162]: > Internal error:   Could not resolve keysym Invalid
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143162]: Errors from xkbcomp are not fatal to the X server
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143015]: [143015:1021/090108.123389:ERROR:bus.cc(392)] Failed to connect to the bus: Could not parse server address: Unknown address type (examples of valid types are "tcp" and on UNIX "unix")
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143015]: [143015:1021/090108.123499:ERROR:bus.cc(392)] Failed to connect to the bus: Could not parse server address: Unknown address type (examples of valid types are "tcp" and on UNIX "unix")
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143015]: [143015:1021/090108.137246:ERROR:bus.cc(392)] Failed to connect to the bus: Could not parse server address: Unknown address type (examples of valid types are "tcp" and on UNIX "unix")
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143183]: /proc/self/exe: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143183]: /proc/self/exe: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[142997]: [2021-10-21 09:01:08.141213] < - ERROR - > xwayland: XCB error: no reply data
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143186]: /proc/self/exe: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-client.so.0)
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143186]: /proc/self/exe: /snap/electron-kiosk-uc20/x1/gnome-platform/usr/lib/x86_64-linux-gnu/libffi.so.7: no version information available (required by /snap/electron-kiosk-uc20/x1/usr/lib/x86_64-linux-gnu/libwayland-server.so.0)
Oct 21 09:01:08 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[143178]: [143178:1021/090108.211055:ERROR:sandbox_linux.cc(374)] InitializeSandbox() called with multiple threads in process gpu-process.
Oct 21 09:02:09 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[142997]: [2021-10-21 09:02:09.803895] < - debug - > mirserver: Handling Terminated from pid=1
Oct 21 09:02:09 SydneyDemo2 systemd[1]: Stopping Service for snap application electron-kiosk-uc20.electron-kiosk-uc20...
Oct 21 09:02:09 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[142997]: [2021-10-21 09:02:09.805319] <information> xwayland: Deiniting xwayland server
Oct 21 09:02:09 SydneyDemo2 electron-kiosk-uc20.electron-kiosk-uc20[142997]: [2021-10-21 09:02:09.905667] <information> xwayland: XWayland stopped
Oct 21 09:02:09 SydneyDemo2 systemd[1]: snap.electron-kiosk-uc20.electron-kiosk-uc20.service: Succeeded.
Oct 21 09:02:09 SydneyDemo2 systemd[1]: Stopped Service for snap application electron-kiosk-uc20.electron-kiosk-uc20.

i’m not sure how this InitializeSandbox() error can occur given the command should have --no-sandbox defined in the wrapper …

Is it normal for $SNAP/gnome-platform to be empty?

no, it should be showing the bind-mounted content of the gnome-3-38 snap (which gets automatically installed and connected)

ogra@pi4-arm64:~$ sudo snap run --shell electron-kiosk-wayland.electron-kiosk-wayland
root@pi4-arm64:/home/ogra$ ls $SNAP/gnome-platform
etc  lib  meta	sbin  snap  usr  var
root@pi4-arm64:/home/ogra$ 

You got two similar repos

I will try electron-kiosk-wayland

the wayland version is still in the works and has some performance issues on the RPi4 (Pi2 and 3 should be fine) … in case you run on that hardware …

Why my snap does not mount gnome-platform?

i’m honestly not sure, it clearly does for me when testing on Ubuntu Core 20 on a Pi4 (as you can see above)