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packages/core/scss/bootstrap/_override.scss

@@ -81,7 +81,8 @@
 // .card-header:first-child {
 // }
 
-// // Well (substitute Well of bootstrap3)
+// TODO: Use .custom-card instead of .well
+// https://redmine.weseek.co.jp/issues/128307
 // .card.well {
 //   min-height: 20px;
 //   padding: $card-spacer-y $card-spacer-x;