I wasn't really happy with the options out there, so I designed my own, also, hopefully for others to enjoy.
It fits my Bambu Lab P1S build plate.
If you need a smaller version for an Ender 3, for example, just message me.
The lid is quite thin, but it does its job. I wouldn't trust the lid if you throw the tray off your desk but it makes it stackable.
The author marked this model as their own original creation.