"THE CONTROL AND ISSUANCE OF BLANK BALLOTS IS KEY."
"Watch the water[mark]."
Ballot watermarks are mentioned on government website CISA for controls within the mail-in voting process
https://www.cisa.gov/sites/default/files/publications/cisa-mail-in-voting-infrastructure-risk-assessment_508.pdf
https://twitter.com/CISAgov/status/1323715899740856329?s=20