meek is broken in Tor Browser 6.0a3
meek does not work any longer in Tor Browser 6.0a3. It seems this is caused by an underlying bug in tor. After some amount of testing and bisecting commit 23b088907fd23da417f5caf2b7b5f664f317ef4a is the first that introduces the new behavior. Trying to start meek with it results in
Mar 10 13:50:53.000 [notice] Ignoring directory request, since no bridge nodes are available yet. Mar 10 13:50:54.000 [notice] Delaying directory fetches: No running bridges
and nothing thereafter: the startup is stalled.