In KDE version 5, the file manager does not work properly

HOW TO REPRODUCE:

When using the "Quick Browser" plugin in Cairo-Dock, no folder or file can be opened, even if ~/.local/share/applications/mimeapps.list is configured with the correct handler.There is no response at all.

gvfs-open, mimeopen, gio open commands work fine using the same handler for "inode/directory"

SYSTEM INFORMATION:

Cairo version: 3.4.1
OS: Ubuntu 19.10 (eoan) + KDE
KDE version: 5.16.5

DEBUG INFORMATION:

debug : (/build/cairo-dock-XfXg2O/cairo-dock-3.4.1/src/gldit/cairo-dock-file-manager.c:_cairo_dock_fm_launch_uri_threaded:118)
  _cairo_dock_fm_launch_uri_threaded (/root)
debug : (/build/cairo-dock-plug-ins-30gRN8/cairo-dock-plug-ins-3.4.1/kde-integration/src/applet-vfs.c:vfs_backend_launch_uri:812)
  vfs_backend_launch_uri (/root)
debug : (/build/cairo-dock-XfXg2O/cairo-dock-3.4.1/src/gldit/cairo-dock-utils.c:cairo_dock_launch_command_full:298)
  cairo_dock_launch_command_full (kioclient exec "/root" , (null))
sh: 1: kioclient: not found

kioclient is not used in KDE5 but kioclient5

FURTHER INFORMATION:

KDE version (4:5) can be retrieved with command:

plasmashell --version | grep -Po '^[^\d.]*\K\d+(?=\.)'

if this command returns a "5", then the "kioclient5" must be used instead of "kioclient". So far, for this bug only line 812 in kde-integration/src/applet-vfs.c has been found incorrect.