Warrior Sword F1 Flurry does not benefit from Bursts traits with only the Immobilize landed on target.
This happens if you press F1 to immobilize a target then swap weapons fast. The target is immobilized and Adrenaline is spent but Bursts traits does not proc with it.
Required Change : F1 Flurry Burst should be considered landed as soon as the target get immobilized.