According to https://blueprints.launchpad.net/ubuntu/+spec/desktop-r-cups-bonjour-browsing a fix to the LibreOffice Print dialog for #1083757 has been released and I observe that the dialog is populated when neither cups-browsed nor cupsd is running. However, I cannot track down where and when the fix first appeared in LibreOffice. Any chance of a clue? Cheers, Brian.