Manifesto is not the right word. Definition: A public declaration of principles, policies, or intentions, especially of a political nature.

Finding something on someone does not make a manifesto, if anything it sounds more like a you got me, or maybe suicide note that he had prepared

Here it is:

“To the Feds, I’ll keep this short, because I do respect what you do for our country. To save you a lengthy investigation, I state plainly that I wasn’t working with anyone. This was fairly trivial: some elementary social engineering, basic CAD, a lot of patience. The spiral notebook, if present, has some straggling notes and To Do lists that illuminate the gist of it. My tech is pretty locked down because I work in engineering so probably not much info there. I do apologize for any strife of traumas but it had to be done. Frankly, these parasites simply had it coming. A reminder: the US has the #1 most expensive healthcare system in the world, yet we rank roughly #42 in life expectancy. United is the [indecipherable] largest company in the US by market cap, behind only Apple, Google, Walmart. It has grown and grown, but as our life expectancy? No the reality is, these [indecipherable] have simply gotten too powerful, and they continue to abuse our country for immense profit because the American public has allwed them to get away with it. Obviously the problem is more complex, but I do not have space, and frankly I do not pretend to be the most qualified person to lay out the full argument. But many have illuminated the corruption and greed (e.g.: Rosenthal, Moore), decades ago and the problems simply remain. It is not an issue of awareness at this point, but clearly power games at play. Evidently I am the first to face it with such brutal honesty.”

Pretty much what everyone suspected already IMO.