From 1e6a88769fb4e0b3731848f21662e2c5cbdc0bce Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Karol=20Ko=C5=82odziej?= <karolkolodziej01@gmail.com>
Date: Thu, 9 Dec 2021 12:23:14 +0100
Subject: [PATCH] Fixed #16673, labels in treeGrid were not destroyed after an
 update.

---
 samples/unit-tests/gantt/treegrid/demo.js |  7 +++++++
 ts/Core/Axis/TreeGridTick.ts              | 12 ++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/samples/unit-tests/gantt/treegrid/demo.js b/samples/unit-tests/gantt/treegrid/demo.js
index 7aebaeba64b..00513c5d1bd 100644
--- a/samples/unit-tests/gantt/treegrid/demo.js
+++ b/samples/unit-tests/gantt/treegrid/demo.js
@@ -516,4 +516,11 @@ QUnit.test('series.data[].collapsed', assert => {
         false,
         'This point should be expanded #13838'
     );
+
+    chart.series[0].setData([], true, true, false);
+    assert.notOk(
+        document.querySelector('.highcharts-label-icon'),
+        `After updating data,
+        the unnecessary label icons should be removed, 16673.`
+    );
 });
diff --git a/ts/Core/Axis/TreeGridTick.ts b/ts/Core/Axis/TreeGridTick.ts
index 84b5931340c..dab3a1c66d8 100644
--- a/ts/Core/Axis/TreeGridTick.ts
+++ b/ts/Core/Axis/TreeGridTick.ts
@@ -466,6 +466,18 @@ namespace TreeGridTick {
             }
         }
 
+        /**
+         * Destroy remaining labelIcon if exist.
+         *
+         * @private
+         * @function Highcharts.Tick#destroy
+         */
+        public destroy(): void {
+            if (this.labelIcon) {
+                this.labelIcon.destroy();
+            }
+        }
+
         /**
          * Expand the grid cell. Used when axis is of type treegrid.
          *