A judge accepted a joint Crown-defence suggestion that Denis-Marc Pelletier be sentenced to nine months in prison.
The 29-year-old Pelletier was facing at least seven charges, including possession of explosives, possession of an arson device and uttering threats.
He was also charged with inciting terrorism, stemming from online musings in the weekend before the Feb. 26 protest.
Pelletier had been detained since his arrest because the Crown opposed bail.
Police said he had two Molotov cocktails in his possession when arrested.
In the messages on social networking site Facebook, he made a reference to "terrorism 2.0."