The conflict seems to be with the Formidable plugin. It is overriding the version of Chosen that comes with Connections, the version in Formidable is much older relatively speaking. Formidable will have to be updated so it uses the new version of Chosen for the two plugin to play nice again. Another option if there is not a Formidable update, check its settings to see if it has an option to turn off autocomplete dropdowns.
If there is not Formidable update and there is not a settings option to turn off autocomplete dropdowns, then the only option would be to roll back both Connections and its template to the versions you had installed previously and wait for formidable to update before updating Connections again.
I hope that helps!