Rated 4 out of 5 stars

I am running WinXP and just installed TB v.3.0.4.
I downloaded and installed TB_Header_Tools_0.7.1-tb3.xpi .
It worked with no problems.

Right-clicking on a message does not bring up "Change Header Details".
Instead, click on Message>Change Header Details.
Installation of the XPI file was kind of tricky.
Click on Tools>Add-ons>Extensions>Install

Four Stars because the Right-click feature is not enabled.