Serious error with Thunderbird 31.0b1 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.

[JavaScript Application]
ReferenceError: BrowserSetForcedCharacterSet is not defined

Disabling Priority Switcher solves this problem.

With Tb 30.0b1, no problem.