So do these non-medical masks we’re all meant to be wearing actually do anything?

Well yes, yes they almost certainly do. Here’s a thread about the current science.

Let’s start by explaining this striking picture of a researcher speaking in a laser scattering chamber.
1/n pic.twitter.com/pm6kA8k0cw

— Jeremy #Masks4All Howard (@jeremyphoward) June 19, 2020