On thingiverse there is a 3d print file of a catch basin that is held with magnets and a shroud for the cutter head that stops the crazy fliers. I used that as a basis and built a rough one from cardboard because I don't have a 3d printer.

Edit: tried to find a link and apparently they are sold on amazon now. https://www.amazon.com/shavings-Catcher-Upgrade-Universal-Trimmer/dp/B07WXK9PXV