This is not a glitch
This is armour doing it's intended purpose
Yes and no. The glitch is either in the combo damage or the combo counter. It's either failing to register the laser as a combo hit, or it's incorrectly factoring in the lasers damage into the combo damage.
Regardless it's a bug in that it creates a situation where users are unclear as to what/why something is happening in the game.
In other words, the bug isn't in the behavior of the characters, the bug/glitch/oversight is in the behavior of the combo counter/damage display.