diff --git a/chrome/content/zotero/overlay.js b/chrome/content/zotero/overlay.js
index 611c3dae8..827ca6f51 100644
--- a/chrome/content/zotero/overlay.js
+++ b/chrome/content/zotero/overlay.js
@@ -2397,7 +2397,7 @@ var ZoteroPane = new function()
 		};
 		window.openDialog('chrome://zotero/content/preferences/preferences.xul',
 			'zotero-prefs',
-			'chrome,titlebar,toolbar,'
+			'chrome,titlebar,toolbar,centerscreen,'
 				+ Zotero.Prefs.get('browser.preferences.instantApply', true) ? 'dialog=no' : 'modal',
 			io
 		);
diff --git a/chrome/content/zotero/preferences/preferences.xul b/chrome/content/zotero/preferences/preferences.xul
index f8d64ad49..ad79a079a 100644
--- a/chrome/content/zotero/preferences/preferences.xul
+++ b/chrome/content/zotero/preferences/preferences.xul
@@ -40,7 +40,7 @@ To add a new preference:
 		in Zotero.Prefs.observe()
 
 -->
-<prefwindow id="zotero-prefs" title="&zotero.preferences.title;" onload="moveToAlertPosition(); init()" onunload="Zotero_Preferences.onUnload()"
+<prefwindow id="zotero-prefs" title="&zotero.preferences.title;" onload="init()" onunload="Zotero_Preferences.onUnload()"
 		windowtype="zotero:pref" xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
 		style="min-height: 600px">
 	
@@ -840,4 +840,4 @@ To add a new preference:
 	]]>
 	</script>
 	<script src="preferences.js"/>
-</prefwindow>
\ No newline at end of file
+</prefwindow>