Developer reply by DW-dev
Rated 4 out of 5 stars
>>> I have this problem too - although a disable/enable also fixes it (but requires two restarts).
Just noticed that if you remove *another* extension and restart then *this* extension works again (for that start).
Starting up on the command line shows this message when it fails, but this is absent when it works:
JavaScript error: chrome://accountcolors/content/accountcolors-3panewindow.js, line 278: InvalidAccessError: A parameter or an operation is not supported by the underlying object
This problem happens when Thunderbird starts slowly, for example, if there are other extensions installed or if the computer is under a heavy load.
A fix for this problem has been designed and tested. A new version of Account Colors will be submitted to the Thunderbird teams tomorrow for review and release, which may take up to a week.
To create your own collections, you must have a Mozilla Add-ons account.