Merge pull request #3018 from haslinghuis/fix-osd-checkbox

Author: blckmn

src/css/dark-theme.less

@@ -520,7 +520,7 @@ progress[value] {
 	input[type='checkbox'] {
 		&:after {
 			line-height: 1.5em;
-			content: '';
+			content: none;
 			display: inline-block;
 			width: 12px;
 			height: 12px;