symphonycms/selectbox_link_field — pull request #42 by lnikkila (2013-07-26 13:32:47+00:00)
Title: Show a message when there are no entries in a section (#18)

Had no problems with this in multiple test scenarios and other related extensions seem to cooperate nicely with this as well. The Multiselect to Checkboxes extension might have a problem with this but it's marked as deprecated so I wouldn't worry about it.