Rated 2 out of 5 stars
Priority Switcher 0.16.4 + Thunderbird 31.0b1
When trying to change character encoding via Option - Encoding - something on message compose window, error dialog appears and encoding cannot be changed.
ReferenceError: BrowserSetForcedCharacterSet is not defined
Disabling Priority Switcher solves this problem.
With Tb 30.0b1, no problem.