When generating a pre-signed URL for download and specifying response-content-disposition to set a target filename, the actual download does not contain the Content-Disposition header therefore the download file does not have the requested filename.

I have confirmed that this works corrected in S3 itself.

I'd be happy to explore a fix if anyone can point me in the right direction/location.
if key:
                object_path = '/' + key
            elif bucket_name_in_host:
                object_path = parsed.path
            else:
                parts = parsed.path[1:].split('/', 1)
                object_path = parts[1] if parts[1][0] == '/' else '/%s' % parts[1]
            version_id = response.headers.get('x-amz-version-id', None)
            send_notifications(method, bucket_name, object_path, version_id)
        
        if method in ('PUT', 'DELETE') and ('/' not in path[1:] or len(path[1:].split('/')[1]) <= 0):
            event_type = (event_publisher.EVENT_S3_CREATE_BUCKET if method == 'PUT'
                else event_publisher.EVENT_S3_DELETE_BUCKET)
            event_publisher.fire_event(event_type, payload={'n': event_publisher.get_hash(bucket_name)})
        
        if method == 'PUT' and parsed.query == 'policy':
            response._content = ''
            response.status_code = 204
            return response
        if response:
            reset_content_length = False
            
            append_cors_headers(bucket_name, request_method=method, request_headers=headers, response=response)
            append_last_modified_headers(response=response)
            
            
            if method == 'PUT' and ('X-Amz-Security-Token=' in path or 'AWSAccessKeyId=' in path):
                response._content = ''
                reset_content_length = True