Reënable day-of-month date grouping option (credit: @tbatchelli)

frontend/src/metabase/lib/formatting.js

@@ -90,6 +90,8 @@ function formatTimeWithUnit(value, unit, options = {}) {
             return moment().hour(value).format("h A");
         case "day-of-week": // Sunday
             return moment().day(value - 1).format("dddd");
+        case "day-of-month":
+            return moment().date(value).format("D");
         case "week-of-year": // 1st
             return moment().week(value).format("wo");
         case "month-of-year": // January

frontend/src/metabase/query_builder/components/TimeGroupingPopover.jsx

@@ -49,7 +49,7 @@ export default class TimeGroupingPopover extends Component {
             // "minute-of-hour",
             "hour-of-day",
             "day-of-week",
-            // "day-of-month",
+            "day-of-month",
             // "day-of-year",
             "week-of-year",
             "month-of-year",