Strange Subliminal Message Experience

I saw, while wide awake, a black bar as if a section of my vision was redacted. I was watching TV at the time, but I could tell that the bar was attached to my vision rather than the TV, likely because of its framing and nearly imperceptible movement. The bar had words over it, and struck me as some kind of instruction that was meant to escape my conscious notice entirely, and act subliminally. This bar was only visible for a flash, likely one frame, but the sudden real sight of it was jarring and memorable.

Even writing about this experience feels automatically laced with paranoia, as if the brain node itself has protection in place, to minimize its significance and avoid notice, and then to make the consciousness not want to bear witness/document it. Even now I am considering not posting this, making both the experience and my seemingly enforced feelings about the experience quite creepy. What could such a message mean? Have subliminal channels advanced to the point where something so precise can be implanted, or did my mind coalesce that message from many sources? If it was my mind, it must have known that the words could not be read in time, so maybe the message was how even such a quick effect can become etched in mind. It was a very strange experience.