What should we do?

When using the File picker component, the user should be informed that the result variable always returns an array of files, either the file picker is configured to support a single file upload or upload of multiple files.

A message is displayed in the Properties panel under the switcher "Support multiple files". Depending on the switcher state it describes that an array returns a single file or multiple files.

Why should we do it?

The File picker component always returns an array of files, even when configured for single file upload.
It can be not clear to users and has led to confusion in the past.