Unknown Errors re Scrivener and Dropbox

[mikethebook]

I was working on a novel in Scrivener 3 on Mac when the two attached error messages came up one after another. I've no idea what they mean or why appeared but I may have hit a few keys together that caused it. I may not. The thing is that I use Dropbox only for storing Scrivener backups (both zipped and unzipped files and the long number looks like it belongs to Scrivener having looked at the contents of a file. But where the two files exist in Dropbox I have no idea, if they actually do. I keep clicking on Cancel but it does no good and rebooting didn't remove the problem. Can anyone help, please? I've written to Scrivener too. Completely non-plussed.