From 565a34e98e9af213073664be0c34417de8bef6a3 Mon Sep 17 00:00:00 2001
From: Heather Arthur <fayearthur@gmail.com>
Date: Fri, 25 Apr 2014 16:50:00 -0400
Subject: [PATCH] Bug 990740 - Make eyedropper movement smoother. r=fitzgen

---
 browser/devtools/eyedropper/eyedropper.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/browser/devtools/eyedropper/eyedropper.js b/browser/devtools/eyedropper/eyedropper.js
index 5b9b104b8030..e2ef93a93b3b 100644
--- a/browser/devtools/eyedropper/eyedropper.js
+++ b/browser/devtools/eyedropper/eyedropper.js
@@ -115,6 +115,8 @@ function Eyedropper(chromeWindow, opts = { copyOnSelect: true }) {
   this._dragging = true;
   this.loaded = false;
 
+  this._mouseMoveCounter = 0;
+
   this.format = Services.prefs.getCharPref(FORMAT_PREF); // color value format
   this.zoom = Services.prefs.getIntPref(ZOOM_PREF);      // zoom level - integer
 
@@ -378,6 +380,11 @@ Eyedropper.prototype = {
       return;
     }
 
+    if (this._OS == "Linux" && ++this._mouseMoveCounter % 2 == 0) {
+      // skip every other mousemove to preserve performance.
+      return;
+    }
+
     this._setCoordinates(event);
     this._drawWindow();