@adrw I see errors from the antivirus plugin.
2020-12-10T02:31:05.000Z {"reqId":"BPffxdeo3xuZ2LQxCCdt","level":3,"time":"2020-12-10T02:31:05+00:00","remoteAddr":"","user":"--","app":"files_antivirus","method":"","url":"--","message":{"Exception":"RuntimeException","Message":"The antivirus executable could not be found at /usr/bin/clamscan","Code":0,"Trace":[{"function":"__construct","class":"OCA\\Files_Antivirus\\Scanner\\LocalClam","type":"->","args":[{"__class__":"OCA\\Files_Antivirus\\AppConfig"},{"__class__":"OC\\AppFramework\\Logger"},{"__class__":"OCA\\Files_Antivirus\\StatusFactory"}]},{"file":"/app/code/lib/private/AppFramework/Utility/SimpleContainer.php","line":101,"function":"newInstanceArgs","class":"ReflectionClass","type":"->","args":[[{"__class__":"OCA\\Files_Antivirus\\AppConfig"},{"__class__":"OC\\AppFramework\\Logger"},{"__class__":"OCA\\Files_Antivirus\\StatusFactory"}]]},{"file":"/app/code/lib/private/AppFramework/Utility/SimpleContainer.php","line":109,"function":"buildClass","class":"OC\\AppFramework\\Utility\\SimpleContainer","type":"->","args":[{"name":"OCA\\Files_Antivirus\\Scanner\\LocalClam","__class__":"ReflectionClass"}]},{"file":"/app/code/lib/private/AppFramework/Utility/SimpleContainer.php","line":126,"function":"resolve","class":"OC\\AppFramework\\Utility\\SimpleContainer","type":"->","args":["OCA\\Files_Antivirus\\Scanner\\LocalClam"]},{"file":"/app/code/lib/private/AppFramework/DependencyInjection/DIContainer.php","line":455,"function":"query","class":"OC\\AppFramework\\Utility\\SimpleContainer","type":"->","args":["OCA\\Files_Antivirus\\Scanner\\LocalClam"]},{"file":"/app/code/lib/private/ServerContainer.php","line":140,"function":"queryNoFallback","class":"OC\\AppFramework\\DependencyInjection\\DIContainer","type":"->","args":["OCA\\Files_Antivirus\\Scanner\\LocalClam"]},{"file":"/app/data/apps/files_antivirus/lib/Scanner/ScannerFactory.php","line":45,"function":"query","class":"OC\\ServerContainer","type":"->","args":["OCA\\Files_Antivirus\\Scanner\\LocalClam"]},{"file":"/app/data/apps/files_antivirus/lib/BackgroundJob/BackgroundScanner.php","line":328,"function":"getScanner","class":"OCA\\Files_Antivirus\\Scanner\\ScannerFactory","type":"->","args":[]},{"file":"/app/data/apps/files_antivirus/lib/BackgroundJob/BackgroundScanner.php","line":115,"function":"scanOneFile","class":"OCA\\Files_Antivirus\\BackgroundJob\\BackgroundScanner","type":"->","args":[{"__class__":"OC\\Files\\Node\\File"}]},{"file":"/app/code/lib/private/BackgroundJob/Job.php","line":52,"function":"run","class":"OCA\\Files_Antivirus\\BackgroundJob\\BackgroundScanner","type":"->","args":[null]},{"file":"/app/code/lib/private/BackgroundJob/TimedJob.php","line":59,"function":"execute","class":"OC\\BackgroundJob\\Job","type":"->","args":[{"__class__":"OC\\BackgroundJob\\JobList"},{"__class__":"OC\\Log"}]},{"file":"/app/code/cron.php","line":127,"function":"execute","class":"OC\\BackgroundJob\\TimedJob","type":"->","args":[{"__class__":"OC\\BackgroundJob\\JobList"},{"__class__":"OC\\Log"}]}],"File":"/app/data/apps/files_antivirus/lib/Scanner/LocalClam.php","Line":43,"CustomMessage":"--"},"userAgent":"--","version":"20.0.1.1"}
I guess it's looking for clamav. Can you make disable that plugin?