Display values in groov View with commas

Is there a way to display values in groov View with commas, e.g. instead of 1921, display 1,921. I have tried various formats in the groov View box for this value gadget (and the formatting help does not elaborate on using commas). Maybe I have missed something in the global settings.
Formatting
Formatting2
Formatting3

At the moment, no. I’m not sure why we don’t display commas* (or whatever locale appropriate grouping character should be used), but we don’t support it at the moment.

* It’s probably because we use this API (GWT NumberFormat) for formatting numbers, and from looking at a quick test it appears that as soon as you provide a custom formatting string grouping breaks.