1st: the concept isn't remotely new.

This article cites the journey of a researcher dating back to the 90's:

https://www.statnews.com/2020/11/10/the-story-of-mrna-how-a-once-dismissed-idea-became-a-leading-technology-in-the-covid-vaccine-race/

This one cites the history of mRNA vaccine research and trials:

https://speakingofresearch.com/2021/08/27/human-mrna-vaccine-trials-in-the-2010s-a-history-lesson-in-animal-research/

This is an article from 2018, citing progress that had, at that point, largely overcome hurdles of instability and inefficiency in vivo delivery of mRNA. It cites the promise of mRNA vaccines, up to and including use as a cancer vaccine.

https://www.nature.com/articles/nrd.2017.243

You ask about what historically constitutes a vaccine, and whether or not it's included RNA injection into humans.

Well, it's clearly happened prior to COVID.

You ask these questions, but haven't expressed any actual problem with them. It is a new technology, but by no means new in the sense that it hasn't undergone decades of research. It has.

Rather than ask multiple questions about the use of RNA, why not present an actual, researched problem with it?

With sources, of course.