--- a/browser/app/profile/firefox.js
+++ b/browser/app/profile/firefox.js
@@ -1030,17 +1030,16 @@ pref("devtools.responsiveUI.enabled", tr
 pref("devtools.debugger.enabled", true);
 pref("devtools.debugger.chrome-enabled", true);
 pref("devtools.debugger.remote-host", "localhost");
 pref("devtools.debugger.remote-autoconnect", false);
 pref("devtools.debugger.remote-connection-retries", 3);
 pref("devtools.debugger.remote-timeout", 20000);
 
 // The default Debugger UI settings
-pref("devtools.debugger.ui.height", 250);
 pref("devtools.debugger.ui.win-x", 0);
 pref("devtools.debugger.ui.win-y", 0);
 pref("devtools.debugger.ui.win-width", 900);
 pref("devtools.debugger.ui.win-height", 400);
 pref("devtools.debugger.ui.stackframes-width", 200);
 pref("devtools.debugger.ui.variables-width", 300);
 pref("devtools.debugger.ui.panes-visible-on-startup", false);
 pref("devtools.debugger.ui.variables-sorting-enabled", true);

--- a/browser/devtools/debugger/DebuggerUI.jsm
+++ b/browser/devtools/debugger/DebuggerUI.jsm
@@ -169,22 +169,16 @@ DebuggerUI.prototype = {
    * @return ChromeDebuggerProcess | null
    *         The chrome debugger instance if it exists, null otherwise.
    */
   getChromeDebugger: function DUI_getChromeDebugger() {
     return '_chromeDebugger' in this ? this._chromeDebugger : null;
   },
 
   /**
-   * Get the preferences associated with the debugger frontend.
-   * @return object
-   */
-  get preferences() Prefs,
-
-  /**
    * Currently, there can only be one debugger per tab.
    * Show an asynchronous notification which asks the user to switch the
    * script debugger to the current tab if it's already open in another one.
    */
   showTabSwitchNotification: function DUI_showTabSwitchNotification() {
     let gBrowser = this.chromeWindow.gBrowser;
     let selectedBrowser = gBrowser.selectedBrowser;
 
@@ -274,17 +268,16 @@ DebuggerPane.prototype = {
 
     let gBrowser = this._win.gBrowser;
     let ownerDocument = gBrowser.parentNode.ownerDocument;
 
     this._splitter = ownerDocument.createElement("splitter");
     this._splitter.setAttribute("class", "devtools-horizontal-splitter");
 
     this._frame = ownerDocument.createElement("iframe");
-    this._frame.height = Prefs.height;
 
     this._nbox = gBrowser.getNotificationBox(this._tab.linkedBrowser);
     this._nbox.appendChild(this._splitter);
     this._nbox.appendChild(this._frame);
 
     let self = this;
 
     this._frame.addEventListener("Debugger:Loaded", function dbgLoaded() {
@@ -321,17 +314,16 @@ DebuggerPane.prototype = {
     if (typeof aCloseCallback == "function") {
       let frame = this._frame;
       frame.addEventListener("unload", function onUnload() {
         frame.removeEventListener("unload", onUnload, true);
         aCloseCallback();
       }, true)
     }
 
-    Prefs.height = this._frame.height;
     this._frame.removeEventListener("Debugger:Unloaded", this.close, true);
     this._nbox.removeChild(this._splitter);
     this._nbox.removeChild(this._frame);
 
     this._splitter = null;
     this._frame = null;
     this._nbox = null;
     this._win = null;
@@ -594,31 +586,17 @@ let L10N = {
 
 XPCOMUtils.defineLazyGetter(L10N, "stringBundle", function() {
   return Services.strings.createBundle(DBG_STRINGS_URI);
 });
 
 /**
  * Shortcuts for accessing various debugger preferences.
  */
-let Prefs = {
-  /**
-   * Gets the preferred height of the debugger pane.
-   * @return number
-   */
-  get height()
-    Services.prefs.getIntPref("devtools.debugger.ui.height"),
-
-  /**
-   * Sets the preferred height of the debugger pane.
-   * @param number aValue
-   */
-  set height(aValue)
-    Services.prefs.setIntPref("devtools.debugger.ui.height", aValue)
-};
+let Prefs = {};
 
 /**
  * Gets the preferred default remote debugging host.
  * @return string
  */
 XPCOMUtils.defineLazyGetter(Prefs, "remoteHost", function() {
   return Services.prefs.getCharPref("devtools.debugger.remote-host");
 });

--- a/browser/devtools/debugger/debugger-controller.js
+++ b/browser/devtools/debugger/debugger-controller.js
@@ -1604,17 +1604,16 @@ let Prefs = {
   map: function P_map(aType, aPropertyName, aPrefName) {
     Object.defineProperty(this, aPropertyName, {
       get: function() this._get(aType, aPrefName),
       set: function(aValue) this._set(aType, aPrefName, aValue)
     });
   }
 };
 
-Prefs.map("Int", "height", "devtools.debugger.ui.height");
 Prefs.map("Int", "windowX", "devtools.debugger.ui.win-x");
 Prefs.map("Int", "windowY", "devtools.debugger.ui.win-y");
 Prefs.map("Int", "windowWidth", "devtools.debugger.ui.win-width");
 Prefs.map("Int", "windowHeight", "devtools.debugger.ui.win-height");
 Prefs.map("Int", "stackframesWidth", "devtools.debugger.ui.stackframes-width");
 Prefs.map("Int", "variablesWidth", "devtools.debugger.ui.variables-width");
 Prefs.map("Bool", "panesVisibleOnStartup", "devtools.debugger.ui.panes-visible-on-startup");
 Prefs.map("Bool", "variablesSortingEnabled", "devtools.debugger.ui.variables-sorting-enabled");