Users Manual
Uploading a file always requires you to confirm a checkbox that grants the configured owner unrestricted rights to it. Leaving it unchecked makes the upload fail. Depending on where you upload from, that checkbox is either shown directly or behind a short confirmation dialog first.
File List module
Click Upload files... in the File List module, or drop files onto it,
and a dialog opens asking you to confirm the checkbox before the actual
upload starts.
Inline file and media fields
Fields with a Select & upload files... button, for example an image or
media field on a content element, show the same confirmation dialog
before the upload starts.
ElementBrowser
The classic upload form inside the ElementBrowser popup, opened for
example via Add media file, shows the checkbox directly next to the
file selector, without an extra dialog.
After a successful upload
Once a file has been uploaded successfully, your user UID is assigned to it.