As I said in the title, a very useful option in VLC is the Debug Logging, one of the interfaces you can add to an instance of VLC. (Tools -> Add Interface -> Debug Logging)
I had this activated by default and it was very useful (I make tests with network cameras) : for every instance, a debug logging appeared...
It was activated by default on all of my VLC versions : the 0.8.6i I installed first, and every Nightly I tested.
Since yesterday, right after installing gdb and libtool to make a bug log, the debug output stopped displaying by default.
I don't know how to make the debug logging window display with VLC at start, is there an environment variable, a shared variable or configuration file to change? It is important to me, it saves me huge chunks of time each day...
I posted it here, because I am on Vista, but I got the same problem with XP and Ubuntu...