ep Street Art in Montreal is very active, officially with all these festivals (Mural, Under Pressure, Canettes de Ruelle...) but also thanks to the artists present in the city, there is always something new to see. It's really interesting. I like Montreal for that.

When you see artists working live during festivals, they already have their idea in a notebook with a lot of sketches, then the main lines are traced on the wall ... so I'm not sure there're a lot of improvisation in these cases.
On the other hand, it must be something else when it is unofficial, errors must be part of the game and often errors give better results 😀