Program Lissandra, e visual bug

03.06.2019 on mid-patch 9.11 I played an ARAM game. On the opposing team there were a Program Lissandra. Whenever Lissandra casted her e ability, a green line would appear across my screen. This only occured when she casted e in vision i think. I asked if any other on my team or the spposite team saw the bug, but they didn't. This happened everytime I saw her use her e.

I have not tried to recreate this bug, so I do not know if this was a one time occurence.