Rated 5 out of 5 stars

Hi Jennifer, yep, great extension, beautiful and deadly!
Buuuuut, after upgrading to 4.0.1 I am justing getting a blank window where the source used to be displayed. (It was working fine before the upgrade.)
Any ideas? Here's hoping!

This review is for a previous version of the add-on (3.02.1-signed.1-signed). 

Tools > Add-ons > Extensions > View Source Chart > Options (Preferences) > select "View Source Charts in a tabbed window"