diff --git a/modules/window.js b/modules/window.js
index 20e822a6..ec47fe46 100644
--- a/modules/window.js
+++ b/modules/window.js
@@ -95,6 +95,13 @@ function TreeStyleTabWindow(aWindow)
 	aWindow.TreeStyleTabService = this;
 
 	XPCOMUtils.defineLazyModuleGetter(aWindow, 'TreeStyleTabBrowser', 'resource://treestyletab-modules/browser.js');
+
+	var DevEdition=this.window.AppConstants.MOZ_DEV_EDITION;
+	if (DevEdition) {
+		var rootelem=this.document.documentElement;
+		rootelem.setAttribute('treestyletab-devedition', true);
+	}
+
 }
 
 TreeStyleTabWindow.prototype = inherit(TreeStyleTabBase, {
diff --git a/skin/classic/treestyletab/base-colors.css b/skin/classic/treestyletab/base-colors.css
index fbfb9ffe..c2d071ee 100644
--- a/skin/classic/treestyletab/base-colors.css
+++ b/skin/classic/treestyletab/base-colors.css
@@ -44,7 +44,7 @@
 	--tst-tab-dropmarker: -moz-dialogtext;
 }
 
-:root[devtoolstheme="dark"] {
+:root[devtoolstheme="dark"][treestyletab-devedition="true"] {
 	--tst-tab-surface: #39424D;
 	--tst-tab-text: white;
 	--tst-tab-border: #5f6670;
diff --git a/skin/classic/treestyletab/square/base.css b/skin/classic/treestyletab/square/base.css
index 3f6dff9a..489364f1 100644
--- a/skin/classic/treestyletab/square/base.css
+++ b/skin/classic/treestyletab/square/base.css
@@ -15,7 +15,7 @@
 	--tst-tabbar-bg: darkgray;
 }
 
-:root[devtoolstheme="dark"] {
+:root[devtoolstheme="dark"][treestyletab-devedition="true"] {
 	--tst-tab-highlighted-base: ThreeDHighlight;
 	--tst-tab-highlighted-highlight: Highlight;
 	--tst-tab-side-border: #39424D;