I included a link to one of the big 6 American propagandists (Fox, ABC, CBS, NBC, CNN, MSNBC) just to show that this is not considered a "conspiracy theory". The link has a stupid autoplay video.
https://abc13.com/health/fda-cdc-call-for-pause-on-j-j-covid-19-vaccine/10511829/
J&J isn't even an mRNA therapy- it's a modified adenovirus with the "might be the covid spike protein, we're not sure" sequence added to it.