Minor Budgie warnings at boot

mei 16 22:09:57 Obelix gsd-color[1746]: could not find device: property match 'XRANDR_name'='DP-1' does not exist
mei 16 22:09:57 Obelix budgie-panel[1838]: unable to open indicator service file directory: Error opening directory “/usr/share/unity/indicators”: No such file or directory
mei 16 22:09:57 Obelix dbus-daemon[1567]: [session uid=1000 pid=1567] Activating service name='ca.desrt.dconf' requested by ':1.49' (uid=1000 pid=1838 comm="budgie-panel " label="unconfined")
mei 16 22:09:57 Obelix gsd-media-keys[1698]: Failed to grab accelerator for keybinding settings:playback-repeat
mei 16 22:09:57 Obelix gsd-media-keys[1698]: Failed to grab accelerator for keybinding settings:playback-random
mei 16 22:09:57 Obelix gsd-media-keys[1698]: Failed to grab accelerator for keybinding settings:rfkill
mei 16 22:09:57 Obelix gsd-media-keys[1698]: Failed to grab accelerator for keybinding settings:hibernate
mei 16 22:09:57 Obelix gsd-media-keys[1698]: Failed to grab accelerator for keybinding settings:rotate-video-lock
mei 16 22:09:57 Obelix dbus-daemon[1567]: [session uid=1000 pid=1567] Successfully activated service 'ca.desrt.dconf'
mei 16 22:09:57 Obelix budgie-panel[1838]: g_file_test: assertion 'filename != NULL' failed
mei 16 22:09:57 Obelix budgie-panel[1838]: ../../../gobject/gsignal.c:1760: parameter 1 of type 'SynapseResultSet' for signal "SynapseDataSink::search-done" is not a value type
mei 16 22:09:57 Obelix budgie-panel[1838]: gdk_window_set_composited: assertion 'GDK_IS_WINDOW (window)' failed
mei 16 22:09:57 Obelix budgie-panel[1838]: GtkBox child SpacerApplet minimum width: -1 < 0 for height 21
mei 16 22:09:57 Obelix budgie-wm.desktop[1817]: Window manager warning: Overwriting existing binding of keysym ff61 with keysym ff61 (keycode 6b).
mei 16 22:09:57 Obelix budgie-wm.desktop[1817]: Window manager warning: Overwriting existing binding of keysym ff61 with keysym ff61 (keycode 6b).
mei 16 22:09:57 Obelix budgie-wm.desktop[1817]: Window manager warning: Overwriting existing binding of keysym ff61 with keysym ff61 (keycode 6b).
mei 16 22:09:57 Obelix gnome-session[1552]: gnome-session-binary[1552]: WARNING: Application 'budgie-panel.desktop' killed by signal 5
mei 16 22:09:57 Obelix gnome-session-binary[1552]: WARNING: Application 'budgie-panel.desktop' killed by signal 5
mei 16 22:09:57 Obelix budgie-panel[1915]: unable to open indicator service file directory: Error opening directory “/usr/share/unity/indicators”: No such file or directory
mei 16 22:09:57 Obelix ModemManager[1329]: <info>  [base-manager] couldn't check support for device '/sys/devices/pci0000:00/0000:00:1f.6': not supported by any plugin
mei 16 22:09:58 Obelix polkitd(authority=local)[1250]: Registered Authentication Agent for unix-session:c1 (system bus name :1.61 [budgie-polkit-dialog], object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US.UTF-8)
mei 16 22:09:58 Obelix gnome-session-binary[1552]: Entering running state
mei 16 22:09:58 Obelix budgie-extras-d[1936]: Binding '<Shift><Alt>dead_grave' failed!
mei 16 22:09:58 Obelix budgie-extras-d[1936]: Binding '<Alt>dead_grave' failed!

I was interested by this one as I thought I could solve it easily: “GtkBox child SpacerApplet minimum width: -1 < 0 for height 21” I checked my panel, it uses 2 spacer applets, both set to “spacer size” 5, so I wonder what else could be wrong?
All the other warnings, no idea what they mean…