One of the first problems with macOS 10.12 Sierra revolved around PDFs created by Fujitsu’s ScanSnap scanners (see “ScanSnap Users Should Delay Sierra Upgrades,” 20 September 2016). Those problems ...

Microsoft has released a cumulative update version KB5004760 that fixes PDF problems where it wouldn't open on Internet Explorer 11 or similar apps, and would only render gray backgrounds in Acrobat.