How to remove trash icon and 'welcome' via cli

[troubleshooter]

Hi all.

I'm trying to adjust raspbian to kiosk mode. GUI not allowed (I'm using ssh).
I've make some adjustments, but now i have to remove 'trash' icon, and change wallpaper.

I hided mouse coursor via unclutter, and disabled panel by commenting everything in /etc/xdg/lxsession/LXDE-pi/autostart except 'pcmanfm' string (to keep wallpaper). But i've no idea how to hide trash icon and how to change wallpaper.
Tryed pcmanfm --set-wallpaper="/my/background/file" - no result. Gives out:

(process:970): Gtk-WARNING **: 21:36:09.334: Locale not supported by C library.
Using the fallback 'C' locale.
Cannot open display:

This is insane. I tried to change locale to en_US, generated new locale.... this is not helps.

Somebody have any advice?

[drooly]

The locale warning has nothing to do with your problem, you can ignore it for now.
TBH I'm having difficulty grasping what's going on.
What are you trying to achieve use a desktop manager, then make it impossible to use it?
Why don't you just remove "pcmanfm -desktop" (or some such) and "lxpanel" from your startup files?