Thanks for responding, Ian! I am aware that I need a special license for automatically uploading existing media.
In my case, I added a photo through the WordPress admin interface after installing the plugin. It ended up in the uploads folder and was displayed in the media library, but never made it to the bucket. A silent failure.
Interestingly, I also played with an Amazon Lightsail instance that comes preinstalled with a Bitnami WordPress package. There, the plugin works immediately. Thus something is wrong with my setup, but at my skill level, I have no hope to understand what!
Same here.
I used the AWS CLI to confirm that the IAM user can copy a file to the bucket. It would be great if an S3 error code or any other information about the error were reported.
