Backed out changeset 513d63765743 (Bug 1808643) for wrong CSS selector. r=backout DONTBUILD

calendar/base/themes/common/widgets/minimonth.css

@@ -77,11 +77,6 @@ calendar-minimonth {
   }
 }
 
-/*
- * Respect system themes when this setting is enabled and not enabled:
- * Calendar: Optimize colors for accessibility
-*/
-:not(:root[lwtheme]) calendar-minimonth,
 :root[systemcolors] calendar-minimonth {
   --mmMainBackground: transparent;
   --mmDayColor: WindowText;