I’ll be at the Velocity Conference in Santa Clara

Later this month, I’ll be at the Velocity Web Performance and Operations conference in Santa Clara. I hope to see some of you there! Beyond my “Lightning Demo” of new Fiddler features, some IE Engineers will be presenting the latest on performance optimization.


“Continue” Link Missing from Certificate Error Page?

A user recently reported that IE11 wasn’t showing the “Continue” link on the certificate error page shown when visiting their 2009-era router’s configuration UI. They were curious why that link wasn’t shown in this instance. The error page’s Continue link is hidden: If the certificate is revoked If the certificate is deemed insecure (e.g. contains…


Swapping out JQuery with Fiddler

This morning, someone asked me to look into a site-compatibility problem on a HTML5 demo site. When loading the site into IE9 and IE10, the F12 Developer Tools’ Script Debugger showed the following error: Now, obviously, IE does support getElementsByTagName, and I confirmed that the page is running in IE9 and IE10 Standards Modes in…


Integrated Windows Authentication

Inside Internet Explorer’s Tools > Internet Options > Advanced dialog, there’s an option named Enable Integrated Windows Authentication: This preference is stored using a REG_DWORD named EnableNegotiate inside HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings. When set to 0x1, Negotiate is enabled. From time to time, users have asked what this option does and why they’d ever want to adjust…


IE9 Standards Mode Accepts only text/css for stylesheets

I recently encountered a blog that isn’t looking right in IE9: The site renders just fine in other browsers, and when the page is put into Compatibility View by ticking the icon in the address bar: What’s going on here?  It’s clear that a stylesheet isn’t being applied, but why not? While IE9’s F12 Developer…


HTTPS and Keep-Alive Connections

As we explore network performance on the “real-world web”, one bad pattern in particular keeps recurring, and it’s not something that our many IE9 Networking Performance Improvements alone will resolve. The bad pattern is the use of Connection: close semantics for HTTPS connections. In this bad pattern, a website allows only a single request and…


Fiddler at MIX 2010

Just a quick little advertisement:   On the heels of the successful Fiddler session at PDC last fall, I’ll be hosting a “mini-session” on Fiddler at the MIX 2010 conference next Wednesday morning. I hope to meet some of you there!   Update 3/23/2010: The video from my talk is now live: http://live.visitmix.com/MIX10/Sessions/FT50.  A big…