Rwanda doesn't have a #trashtag but on every last Saturday of the month it is mandatory for every adult to participate in "Umuganda" which means "coming together in common purpose", where people clean the streets together.

https://media.npr.org/assets/img/2018/07/12/gettyimages-549358801-1-b92f8d91276bb45737c4973142eeddc16e376e07-s1600-c85.jpg