HttpWatch has been updated to support Firefox 15 and add some new features:

• Supports SPDY Version 3
• New SPDY Version column
• Improved handling of images with transparency
• High DPI Awareness for Windows 7

SPDY Version 3 is an updated version of the SPDY protocol and includes some performance related changes such as improved header compression. These changes have been included in Firefox 15 but are not enabled by default. To try out SPDY version 3 you need to enable the network.http.spdy.enabled.v3 setting in about:config:

There’s also a new SPDY Version column that you can add in HttpWatch 8.5 to show which version of the protocol is being used. Here’s a screen shot from HttpWatch looking at the HTTPS version of wordpress.com. You can see that wordpress uses version 2 of the SPDY protocol but the Google resources use SPDY version 3: