Below is a list of sites about the integrity of research, one of the 8 pillars of Open Science
Retraction watch: blog edited by the Center for Scientific Integrity, reports retractions of scientific articles. It feeds a list of retractions, with a section reserved for Covid-19 themed retractions, a list of hijacked journals, a list of papers and peer-reviews written with artificial intelligence systems
Pub Peer: platform that allows the publication of post peer-review publications also in an anonymous manner, often identifying problems related to images or methodologies used
Science Integrity Digest: blog by Elizabeth Bik, microbiologist specialized in identifying images and graphs copied from different scientific journals, a clue that reveals the illicit practice of paper mills and review mills
For better science: site on research integrity and ethics in the biomedical field by Leonid Schneider, independent scientific journalist