Created attachment 117187 [details]
Stalled on 'Requesting Firmware...'

SUMMARY
AtCore_Test_Client-1.0.0-x86_64.AppImage does not recognize Ender-3 printer (Marlin based)

STEPS TO REPRODUCE
1. Run neon-devedition-gitunstable-current.iso
2. Attach Ender-3 printer via USB
3. sudo Downloads/AtCore_Test_Client-1.0.0-x86_64.AppImage
4. Click "Connect"

OBSERVED RESULT
me@host:~$ sudo Downloads/AtCore_Test_Client-1.0.0-x86_64.AppImage 
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
org.kde.atelier.core: Atcore state changed from [ AtCore::STATES(18240336) ] to [ AtCore::STATES(DISCONNECTED) ]
org.kde.atelier.core.plugin: Lookin for plugins in  "/home/travis/build/sithlord48/atcore/src/plugins"
org.kde.atelier.core.plugin: Lookin for plugins in  "lib/x86_64-linux-gnu/plugins/AtCore"
org.kde.atelier.core.plugin: Lookin for plugins in  "/opt/qt59/plugins/AtCore"
org.kde.atelier.core.plugin: Lookin for plugins in  "plugins"
org.kde.atelier.core.plugin: Lookin for plugins in  "/tmp/.mount_AtCore9HUfZG/usr/plugins/AtCore"
org.kde.atelier.core.plugin: Valid path for plugins found !
org.kde.atelier.core.plugin: QDir( "/tmp/.mount_AtCore9HUfZG/usr/plugins/AtCore" , nameFilters = { "*" },  QDir::SortFlags( Name | IgnoreCase ) , QDir::Filters( Dirs|Files|Drives|AllEntries ) )
org.kde.atelier.core.plugin: plugin dir: QDir( "/tmp/.mount_AtCore9HUfZG/usr/plugins/AtCore" , nameFilters = { "*" },  QDir::SortFlags( Name | IgnoreCase ) , QDir::Filters( Dirs|Files|Drives|AllEntries ) )
org.kde.atelier.core: Found plugin file "libaprinter.so"
org.kde.atelier.core: "plugins[aprinter]=/tmp/.mount_AtCore9HUfZG/usr/plugins/AtCore/libaprinter.so"
org.kde.atelier.core: Found plugin file "libgrbl.so"
org.kde.atelier.core: "plugins[grbl]=/tmp/.mount_AtCore9HUfZG/usr/plugins/AtCore/libgrbl.so"
org.kde.atelier.core: Found plugin file "libmarlin.so"
org.kde.atelier.core: "plugins[marlin]=/tmp/.mount_AtCore9HUfZG/usr/plugins/AtCore/libmarlin.so"
org.kde.atelier.core: Found plugin file "librepetier.so"
org.kde.atelier.core: "plugins[repetier]=/tmp/.mount_AtCore9HUfZG/usr/plugins/AtCore/librepetier.so"
org.kde.atelier.core: Found plugin file "libsmoothie.so"
org.kde.atelier.core: "plugins[smoothie]=/tmp/.mount_AtCore9HUfZG/usr/plugins/AtCore/libsmoothie.so"
org.kde.atelier.core: Found plugin file "libsprinter.so"
org.kde.atelier.core: "plugins[sprinter]=/tmp/.mount_AtCore9HUfZG/usr/plugins/AtCore/libsprinter.so"
org.kde.atelier.core: Found plugin file "libteacup.so"
org.kde.atelier.core: "plugins[teacup]=/tmp/.mount_AtCore9HUfZG/usr/plugins/AtCore/libteacup.so"
org.kde.atelier.core: Atcore state changed from [ AtCore::STATES(DISCONNECTED) ] to [ AtCore::STATES(CONNECTING) ]

EXPECTED RESULT
Recognizes the printer

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 5.14.80 (system)
(available in About System)
KDE Plasma Version: What comes with AtCore_Test_Client-1.0.0-x86_64.AppImage
KDE Frameworks Version: What comes with AtCore_Test_Client-1.0.0-x86_64.AppImage
Qt Version: What comes with AtCore_Test_Client-1.0.0-x86_64.AppImage

ADDITIONAL INFORMATION
See screenshot