Barricades and bonfires in the streets, what happens in Catalonia?

Catalonia lives days of protests after the condemnation of the Spanish Supreme Court to several Catalan leaders for sedition. Everything goes back to the referendum for the independence of the regional region in 2017, considered illegal by Spain. The president of the acting Spanish Government, Pedro Sánchez, appealed to the president of the Generalitat of Catalonia.