A Senate panel documented an effort largely undetected by state and federal officials at the time. But its report was so heavily redacted that key lessons for 2020 were blacked out.
https://www.nytimes.com/2019/07/25/us/politics/russian-hacking-elections.html
http://day.kyiv.ua/ru/blog/politika/moskovskoe-razocharovanie
https://carnegie.ru/commentary/79564
https://lb.ua/world/2019/07/25/433073_russiagate_viyshov_lyudey_yak_ssha.html
http://www.kasparov.ru/material.php?id=5D39CD4EE50CA
http://www.rosbalt.ru/world/2019/07/25/1793492.html
https://jamestown.org/program/belarus-russia-integration-further-tightening-looks-unlikely/