After the terror attacks in Brussels on Tuesday you will have seen a number of people change their Facebook profile picture to feature the Belgium flag to show support to all those who were killed and injured.

The option to change your picture to a flag overlay was not as widely rolled out as it was for the Paris attacks in November. 

Facebook is working on allowing Pages to build temporary profile overlays, which will allow people to set a new profile photo that will last a set amount of time before reverting back. Through this feature users will be able to choose when they want to support a cause or show solidarity.