What makes Catalina make a shell script quarantined?
Solution 1:
This can be fixed in BBEdit by doing this:
Check and see whether sandbox access is allowed (in BBEdit's "Application" preferences). If it is not, allow it and I think that will solve this for you.
Source: https://twitter.com/siegel/status/1161105160212484097
Solution 2:
macOS will automatically quarantine executable files that are written by sandboxed applications, unless the file being written is within a directory for which the application has a "sandbox extension".
More on this is available here: https://www.barebones.com/support/bbedit/quarantine.html