Protest requires a all sorts of different people filling in many different roles in order to be effective. There are the people on the ground, of course, the ones you see in photos.
And then there is the behind the scenes support: supplies, jail support, and monetary backing. In order for direct action to succeed and be sustainable, all those pieces need to be in place.
For people who cannot be on the ground, donating money to a bail fund is a tangible way to support protesters. And thanks to a Twitter trend, thousands of people have done just that for the folks in Minneapolis protesting the murder of George Floyd at the hands of a police officer.