Commented Issue: ToolkitScriptManager (without CombineScriptsHandlerUrl) and Page Trace=true conflict [11901]

Probably because the second fetch of the page to get the combined script file ends up including Trace output. Probably workarounds: set CombineScriptsHandlerUrl OR CombineScripts=false.
Comments: I have also had this issue and I am already using a handler defined in CombineScriptsHandlerURL, so this one workaround does not work. With Page.Trace="true", ToolkitScriptManager CombineScripts="true", I get all of the Trace markup injected at the end of the script returned from CombineScriptsHandler.ashx. It seems I have to choose between combining scripts or having Trace on.... example excerpt: //END ModalPopup.ModalPopupBehavior.js if(typeof(Sys)!=='undefined')Sys.Application.notifyScriptLoaded(); (function() {var fn = function() {$get("ScriptManager1_HiddenField").value += ';;AjaxControlToolkit, Version=4.1.60623.0, Culture=neutral, PublicKeyToken=28f01b0e84b6d53e:en-GB:187c1d17-2715-476f-9eeb-4fd46e2849ea:de1feab2:f9cec9bc:35576c48:f2c8e708:720a52bf:589eaa30:698129cf:e148b24b:a67c2700:ab09e3fe:87104b7c:8613aea7:3202a5a2:be6fb298';Sys.Application.remove_load(fn);};Sys.Application.add_load(fn);})(); <div id="__asptrace"> <style type="text/css"> span.tracecontent b { color:white } span.tracecontent { background-color:white; color:black;font: 10pt verdana, arial; }