Translation:They always look down, while they work.
I suppose the comma is put in between clauses, especially if one of the clauses is subordinate.
Is there some strange convention in Danish that requires a comma in this sentence?
Unfortunately they changed the rules of commas a few times while Bjarke and I went to school, so we barely a clue about where to use it. All the sentences with correct commas are properly made by Sofia.
Conversely, all the English sentences with a million (incorrect) commas are properly also made by Sofia :D