diff -r 000000000000 -r 6474c204b198 browser/themes/shared/devtools/eyedropper.css
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/themes/shared/devtools/eyedropper.css	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,45 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#canvas {
+  image-rendering: -moz-crisp-edges;
+  cursor: none;
+  border: 3px solid #E0E0E0;
+  border-radius: 50%;
+}
+
+#canvas-overflow {
+  overflow: hidden;
+  width: 96px;
+  height: 96px;
+}
+
+#color-preview {
+  width: 16px;
+  height: 16px;
+  box-shadow: 0px 0px 0px black;
+  border: solid 1px #fff;
+  margin: 3px;
+}
+
+#color-value-box {
+  background-color: #E0E0E0;
+  border-radius: 1px;
+  width: 150px;
+}
+
+#color-value {
+  padding: 0.3em;
+  text-shadow: 1px 1px 1px #fff;
+}
+
+#color-value.highlight {
+  font-family: inherit;
+}
+
+window {
+  /* inexplicably, otherwise background shows up on Linux */
+  border: 1px solid transparent;
+  background-color: transparent;
+}