^ I found this information:
"#R4BIA| “Rabaa sign” done by raising four fingers has become the symbol of the massacre in Egypt and Rabaa al-Adawiya Square where the anti-coup protests take place.
“Rabaa” meaning four or the fourth in Arabic has become the sign of anti-coup protests in Egypt. Just a few hours before the massacre on August 14, anti-coup protesters in Egypt tried to voice their demands to the world by raising their four fingers."