diff --git a/browser/devtools/debugger/debugger-controller.js b/browser/devtools/debugger/debugger-controller.js
index 720b74b2a657..93bdedcefdd6 100644
--- a/browser/devtools/debugger/debugger-controller.js
+++ b/browser/devtools/debugger/debugger-controller.js
@@ -11,6 +11,7 @@ const Cu = Components.utils;
 
 const FRAME_STEP_CACHE_DURATION = 100; // ms
 const DBG_STRINGS_URI = "chrome://browser/locale/devtools/debugger.properties";
+const SCRIPTS_URL_MAX_LENGTH = 64; // chars
 const SYNTAX_HIGHLIGHT_MAX_FILE_SIZE = 1048576; // 1 MB in bytes
 
 Cu.import("resource:///modules/source-editor.jsm");
@@ -1088,7 +1089,12 @@ SourceScripts.prototype = {
    *         The simplified label.
    */
   getScriptLabel: function SS_getScriptLabel(aUrl, aHref) {
-    return this._labelsCache[aUrl] || (this._labelsCache[aUrl] = this._trimUrl(aUrl));
+    let label = this._trimUrl(aUrl);
+    if (label.length > SCRIPTS_URL_MAX_LENGTH) {
+      let ellipsis = Services.prefs.getComplexValue("intl.ellipsis", Ci.nsIPrefLocalizedString);
+      label = label.substring(0, SCRIPTS_URL_MAX_LENGTH) + ellipsis.data;
+    }
+    return this._labelsCache[aUrl] || (this._labelsCache[aUrl] = label);
   },
 
   /**
diff --git a/browser/devtools/debugger/test/browser_dbg_propertyview-01.js b/browser/devtools/debugger/test/browser_dbg_propertyview-01.js
index 6d36ffe6aaef..ea79275b5105 100644
--- a/browser/devtools/debugger/test/browser_dbg_propertyview-01.js
+++ b/browser/devtools/debugger/test/browser_dbg_propertyview-01.js
@@ -40,6 +40,9 @@ function testScriptLabelShortening() {
     is(ss.trimUrlQuery("a/b/c.d?test=1&random=4#reference"), "a/b/c.d",
       "Trimming the url query isn't done properly.");
 
+    let ellipsis = Services.prefs.getComplexValue("intl.ellipsis", Ci.nsIPrefLocalizedString);
+    let nanana = new Array(20).join(NaN);
+
     let urls = [
       { href: "http://some.address.com/random/", leaf: "subrandom/" },
       { href: "http://some.address.com/random/", leaf: "suprandom/?a=1" },
@@ -62,7 +65,9 @@ function testScriptLabelShortening() {
       { href: "file://random/", leaf: "script_t2_3.js&b" },
       { href: "resource://random/", leaf: "script_t3_1.js#id?a=1&b=2" },
       { href: "resource://random/", leaf: "script_t3_2.js?a=1&b=2#id" },
-      { href: "resource://random/", leaf: "script_t3_3.js&a=1&b=2#id" }
+      { href: "resource://random/", leaf: "script_t3_3.js&a=1&b=2#id" },
+
+      { href: nanana, leaf: "Batman!" + "{trim me, now and forevermore}" }
     ];
 
     urls.forEach(function(url) {
@@ -121,6 +126,9 @@ function testScriptLabelShortening() {
       ok(gDebugger.DebuggerView.Scripts.containsLabel("script_t3_3.js"),
         "Script (14) label is incorrect.");
 
+      ok(gDebugger.DebuggerView.Scripts.containsLabel(nanana + "Batman!" + ellipsis),
+        "Script (15) label is incorrect.");
+
       is(vs._scripts.itemCount, urls.filter(function(url) !url.dupe).length,
         "Didn't get the correct number of scripts in the list.");
 
diff --git a/browser/themes/gnomestripe/devtools/debugger.css b/browser/themes/gnomestripe/devtools/debugger.css
index fcd0dc6f4c22..426f5882c56b 100644
--- a/browser/themes/gnomestripe/devtools/debugger.css
+++ b/browser/themes/gnomestripe/devtools/debugger.css
@@ -17,7 +17,6 @@
 }
 
 #scripts {
-  max-width: 350px;
   min-width: 150px;
 }
 
diff --git a/browser/themes/pinstripe/devtools/debugger.css b/browser/themes/pinstripe/devtools/debugger.css
index c440c7c6e71a..1784637785aa 100644
--- a/browser/themes/pinstripe/devtools/debugger.css
+++ b/browser/themes/pinstripe/devtools/debugger.css
@@ -19,7 +19,6 @@
 }
 
 #scripts {
-  max-width: 350px;
   min-width: 150px;
 }
 
diff --git a/browser/themes/winstripe/devtools/debugger.css b/browser/themes/winstripe/devtools/debugger.css
index 694c98af4c31..d7e5170be457 100644
--- a/browser/themes/winstripe/devtools/debugger.css
+++ b/browser/themes/winstripe/devtools/debugger.css
@@ -17,7 +17,6 @@
 }
 
 #scripts {
-  max-width: 350px;
   min-width: 150px;
 }