Add helper functions for confirmation status

app/helpers/is-confirmed-contribution.js

@@ -0,0 +1,15 @@
+import Helper from '@ember/component/helper';
+import { inject as service } from '@ember/service';
+import { alias } from '@ember/object/computed';
+
+export default Helper.extend({
+
+  kredits: service(),
+  currentBlock: alias('kredits.currentBlock'),
+
+  compute([contribution]) {
+    return !contribution.vetoed &&
+           (contribution.confirmedAt <= this.currentBlock);
+  }
+
+});