What is the purpose of the submenu?
In older versions (e.g. 2.06) it was possible, to click responses to have all responses and a filtering of startlanguage (?).

If a start language filtering is still the purpose, that seems to be not working (demo.limesurvey.org Version 3.14.5).

When e.g clicking Frensh I get all responses (which were conducted in different languages).
Or is the submenu for selecting the column headers language?