Use a temporary overlay that the city’s billboard software can’t detect. Hack into the control panel, pull the “render” buffer, and drop a small, low‑contrast bubble‑letter layer on top. Keep the pixels thin and spaced; the algorithm will ignore it as noise. Then hit refresh before the system sweeps. It’s a quick glitch, not a permanent hack, so you get your manifesto on the skyline without it getting erased. Just remember to unplug before the night patrol comes by.