Just upgraded the wbm-virtual-server package to 4.13-1 and then tried a backup of a virtual server. Got this error:
Dumping MySQL database api .. .. dump failed!
mysqldump: Got error: 1045: Access denied for user 'api'@'localhost' (using password: YES) when trying to connect Backup failed! See the progress output above for the reason why.
The backup worked fine yesterday before the Virtualmin package update this morning.