Triburst Device adds 5 strength to the attack unit in front of it and Bifurcate Core distributes its strength to the two other lanes instead of accumulating on itself. But when Triburst Device adds strength to it the strength stays on it and is not distributed. Seems like a bug.

(Also the description of how Triburst Device works needs to be edited so that it's clear it affects the unit in front of it, not at the front of the ship.)