Tor's log messages seem to get emitted twice on start-up in Tor Browser 4.5-alpha-x
Starting with 4.5-alpha-1 it seems tor is started twice and reading at least its configuration files twice, too:
Dec 19 10:56:17.739 [notice] Tor v0.2.6.1-alpha (git-d0cec68f342992b4) running on Linux with Libevent 2.0.21-stable, OpenSSL 1.0.1i and Zlib 1.2.8.
Dec 19 10:56:17.739 [notice] Tor can't help you if you use it wrong! Learn how to be safe at https://www.torproject.org/download/download#warning
Dec 19 10:56:17.739 [notice] This version is not a stable Tor release. Expect more bugs than usual.
Dec 19 10:56:17.739 [notice] Read configuration file "/home/thomas/Arbeit/Tor/TBB/Dev_Test/TBB/tor-browser_en-US/Browser/TorBrowser/Data/Tor/torrc-defaults".
Dec 19 10:56:17.739 [notice] Read configuration file "/home/thomas/Arbeit/Tor/TBB/Dev_Test/TBB/tor-browser_en-US/Browser/TorBrowser/Data/Tor/torrc".
Dec 19 10:56:17.752 [notice] Opening Socks listener on 127.0.0.1:9150
Dec 19 10:56:17.753 [notice] Opening Control listener on 127.0.0.1:9151
Dec 19 10:56:17.739 [notice] Tor v0.2.6.1-alpha (git-d0cec68f342992b4) running on Linux with Libevent 2.0.21-stable, OpenSSL 1.0.1i and Zlib 1.2.8.
Dec 19 10:56:17.739 [notice] Tor can't help you if you use it wrong! Learn how to be safe at https://www.torproject.org/download/download#warning
Dec 19 10:56:17.739 [notice] This version is not a stable Tor release. Expect more bugs than usual.
Dec 19 10:56:17.739 [notice] Read configuration file "/home/thomas/Arbeit/Tor/TBB/Dev_Test/TBB/tor-browser_en-US/Browser/TorBrowser/Data/Tor/torrc-defaults".
Dec 19 10:56:17.739 [notice] Read configuration file "/home/thomas/Arbeit/Tor/TBB/Dev_Test/TBB/tor-browser_en-US/Browser/TorBrowser/Data/Tor/torrc".
Dec 19 10:56:17.752 [notice] Opening Socks listener on 127.0.0.1:9150
Dec 19 10:56:17.753 [notice] Opening Control listener on 127.0.0.1:9151
Dec 19 10:56:17.000 [notice] Parsing GEOIP IPv4 file /home/thomas/Arbeit/Tor/TBB/Dev_Test/TBB/tor-browser_en-US/Browser/TorBrowser/Data/Tor/geoip.
Dec 19 10:56:18.000 [notice] Parsing GEOIP IPv6 file /home/thomas/Arbeit/Tor/TBB/Dev_Test/TBB/tor-browser_en-US/Browser/TorBrowser/Data/Tor/geoip6.
Dec 19 10:56:18.000 [notice] Bootstrapped 0%: Starting
Doing that once should be enough. Putting that tentatively in the tbb-torbutton section as I guess Arthur's circuit UI related code might be involved here.