The term has been used on Twitter more than 11 million times since last April, the platform said, with usage again spiking after the Myanmar coup.
The military regime there has imposed overnight internet shutdowns and blanket mobile data restrictions to try and bring weeks of unrest to heel.
It has also directed local telecom service providers to block access to social media sites, which protesters have skirted by using virtual private networks and foreign SIM cards.
“We strongly believe that having access to the free and #OpenInternet is an essential right and remain a staunch defender and advocate of free expression and condemn #InternetShutdowns,” Twitter said in its announcement of the new emoji.
Thursday’s move follows similar recognition by Twitter in recent years of the #MeToo and #BlackLivesMatter social movements, after the respective global campaigns against sexual abuse and in support of racial justice.