Unnecessary connection to check.torproject.org
On every startup, HTTPS-Everywhere version 3.1.4 (Firefox 20.0) connects to check.torproject.org (HTTPS). This automatic connection doesn't happen when HTTPS-Everywhere is disabled. By looking at the source code of HTTPS-Everywhere, it seems to me that the purpose of this connection is to check whether Firefox is connected through a TOR proxy.
This TOR check is not needed when SSL-Observatory is disabled, which is the case here.