I'm not sure if you just didn't add it to the text, but is there no title for the job offer? Something like "React dev (m/w/d), mostly Frontend, Fullstack appreciated" (along these lines, can be done better surely).
Also while some parts look like good offers to some people, they may be intimidating to others. For example "take share of leader's responsibilities" - not everyone may like to do that. Now it can be that you don't want people who shy away from this, but if you don't care and it's entirely optional, then say it is optional.
Same for backend. I have seen a lot of offers that sound like pure Frontend, but during first interview it becomes obvious that it's actually full stack. So be clear if it's a fullstack position with focus on frontend, or a frontend position, preferably in the title already.
My 2cents:) Good luck with your applicants!