From 24627f0b3ed42193165a8f9dd4031abcab7b342f Mon Sep 17 00:00:00 2001
From: Sam El-Husseini <sam.elhusseini@gmail.com>
Date: Tue, 19 Nov 2019 08:41:00 -0800
Subject: [PATCH] Fix zelos flickering in flyout (#3448)

---
 core/flyout_base.js                 |  8 ++++----
 core/renderers/zelos/path_object.js | 14 ++++++++------
 2 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/core/flyout_base.js b/core/flyout_base.js
index 99d22fbc8..85b69cd77 100644
--- a/core/flyout_base.js
+++ b/core/flyout_base.js
@@ -585,13 +585,13 @@ Blockly.Flyout.prototype.addBlockListeners_ = function(root, block, rect) {
       this.blockMouseDown_(block)));
   this.listeners_.push(Blockly.bindEventWithChecks_(rect, 'mousedown', null,
       this.blockMouseDown_(block)));
-  this.listeners_.push(Blockly.bindEvent_(root, 'mouseover', block,
+  this.listeners_.push(Blockly.bindEvent_(root, 'mouseenter', block,
       block.addSelect));
-  this.listeners_.push(Blockly.bindEvent_(root, 'mouseout', block,
+  this.listeners_.push(Blockly.bindEvent_(root, 'mouseleave', block,
       block.removeSelect));
-  this.listeners_.push(Blockly.bindEvent_(rect, 'mouseover', block,
+  this.listeners_.push(Blockly.bindEvent_(rect, 'mouseenter', block,
       block.addSelect));
-  this.listeners_.push(Blockly.bindEvent_(rect, 'mouseout', block,
+  this.listeners_.push(Blockly.bindEvent_(rect, 'mouseleave', block,
       block.removeSelect));
 };
 
diff --git a/core/renderers/zelos/path_object.js b/core/renderers/zelos/path_object.js
index ba613164c..537e015a9 100644
--- a/core/renderers/zelos/path_object.js
+++ b/core/renderers/zelos/path_object.js
@@ -103,12 +103,14 @@ Blockly.zelos.PathObject.prototype.flipRTL = function() {
 Blockly.zelos.PathObject.prototype.updateSelected = function(enable) {
   this.setClass_('blocklySelected', enable);
   if (enable) {
-    this.svgPathSelected_ =
-      /** @type {!SVGElement} */ (this.svgPath.cloneNode(true));
-    this.svgPathSelected_.setAttribute('fill', 'none');
-    this.svgPathSelected_.setAttribute('filter',
-        'url(#' + this.constants_.highlightGlowFilterId + ')');
-    this.svgRoot.appendChild(this.svgPathSelected_);
+    if (!this.svgPathSelected_) {
+      this.svgPathSelected_ =
+        /** @type {!SVGElement} */ (this.svgPath.cloneNode(true));
+      this.svgPathSelected_.setAttribute('fill', 'none');
+      this.svgPathSelected_.setAttribute('filter',
+          'url(#' + this.constants_.highlightGlowFilterId + ')');
+      this.svgRoot.appendChild(this.svgPathSelected_);
+    }
   } else {
     if (this.svgPathSelected_) {
       this.svgRoot.removeChild(this.svgPathSelected_);