The goal is to allow an autocomplete field that uses taxonomy terms, and which allows multiple entries from the same taxonomy list – for example a list of names & contact info for a field that allows "add all that apply." This works for a text field configured for autocomplete and "unlimited" values. It also works when the source is the User list. However with taxonomy term lists, the "unlimited values" choice does not produce the usual "add another item" option. Is there a way to resolve this? (We want to be able to draw from a taxonomy list, to avoid inconsistencies in how a user might enter names and contact info.)
Problem solved by installation of the Taxonomy Single Tag module and the patch from #6 of this thread. Answer provided by "Poieo" on drupal.org. I have applied this and it is working as desired. However I noticed that without the patch, I was getting errors not only with the new field where the "Single tag autocomplete text field" widget was applied, but also with other fields allowing multiple-item adding – even though they were neither autocomplete nor based on taxonomy terms.