[nemo@Jolla harbour-debota]$ xdg-open /usr/share/applications/voicecall-ui.desktop
START /usr/bin/invoker -t qt5 -s /usr/bin/sailfish-office /usr/share/applications/voicecall-ui.desktop
invoker: error: Application's name is not defined.

Usage: invoker [options] [--type=TYPE] [file] [args]

Launch applications compiled as a shared library (-shared) or
a position independent executable (-pie) through mapplauncherd.

TYPE chooses the type of booster used. Qt-booster may be used to
launch anything. Possible values for TYPE:
  qt5                    Launch a Qt 5 application.
  qtquick2               Launch a Qt Quick 2 (QML) application.
  silica-qt5             Launch a Sailfish Silica application.
  generic                Launch any application, even if it's not a library.

Options:
  -d, --delay SECS       After invoking sleep for SECS seconds
                         (default 0).
  -r, --respawn SECS     After invoking respawn new booster after SECS seconds
                         (default 3, max 10).
  -w, --wait-term        Wait for launched process to terminate (default).
  -n, --no-wait          Do not wait for launched process to terminate.
  -G, --global-syms      Places symbols in the application binary and its
                         libraries to the global scope.
                         See RTLD_GLOBAL in the dlopen manual page.
  -s, --single-instance  Launch the application as a single instance.
                         The existing application window will be activated
                         if already launched.
  -o, --keep-oom-score   Notify invoker that the launched process should inherit oom_score_adj
                         from the booster. The score is reset to 0 normally.
  -T, --test-mode        Invoker test mode. Also control file in root home should be in place.
  -F, --desktop-file     Desktop file of the application.
  -h, --help             Print this help.

Example: invoker --type=qt5 /usr/bin/helloworld

[W] GKeyFileWrapper::stringValue:157 - Could not read value: "Key file does not have key 'X-Maemo-Object-Path'"
[W] GKeyFileWrapper::stringValue:157 - Could not read value: "Key file does not have key 'X-Maemo-Fixed-Args'"
[W] GKeyFileWrapper::stringValue:157 - Could not read value: "Key file does not have key 'X-Maemo-Object-Path'"
[W] GKeyFileWrapper::stringValue:157 - Could not read value: "Key file does not have key 'X-Maemo-Fixed-Args'"
[nemo@Jolla harbour-debota]$