thunderbird: manual accounts have cache disabled but active

I have the addon installed. I created some test accounts manually. The cache option is disabled, but in "active" state.

This is probably a bug, we should either:

1. Do not touch manually created "leap" accounts (is this possible? can we know which accounts were created by the addon?)
2. Disable and deactivate cache option for all "leap" accounts.

Whatever is easier maybe.

(from redmine: created on 2013-12-19, closed on 2014-06-03)