FIX: disable flagging hidden posts

app/assets/javascripts/discourse/widgets/post-menu.js.es6

@@ -109,7 +109,7 @@ registerButton("like-count", attrs => {
 });
 
 registerButton("flag", attrs => {
-  if (attrs.canFlag) {
+  if (attrs.canFlag && !attrs.hidden) {
     return {
       action: "showFlags",
       title: "post.controls.flag",

test/javascripts/widgets/post-test.js.es6

@@ -389,6 +389,16 @@ widgetTest(`flagging: can't flag`, {
   }
 });
 
+widgetTest(`flagging: can't flag when post is hidden`, {
+  template: '{{mount-widget widget="post" args=args}}',
+  beforeEach() {
+    this.set("args", { canFlag: true, hidden: true });
+  },
+  test(assert) {
+    assert.ok(this.$("button.create-flag").length === 0);
+  }
+});
+
 widgetTest(`read indicator`, {
   template: '{{mount-widget widget="post" args=args}}',
   beforeEach() {