I had this issue the first time I booted up 10.4.2 with a fresh template. then i closed and reopened and somehow I got it to work, but only after increasing the size of the mixer window so that it pretty much covers the whole screen, so that there is enough room after Edit, Options, View ans also Single/Tracks All, finally when there is enough real estate, you will be able to see.
On this topic, i find this to be a great idea very poorly implemented at present. My bigger gripe is that you can’t enable/disable Sends On Faders from the Tracks Window! (Where i spend most of my time). Whenever I want to use it I have to click on the top bar of the Mixer Window to focus it, then use key command or button to enable it, then go back to Tracks Window, then do my Send Fader moves, then go back to the Mixer Window, then disable the feature, then finlaly go back to the Tracks Window. Logic has programmed this under the assumption that most people do most of their work in the Mixer window, and in my experience this simply isn’t the case.
i’ve already ranted to the Feedback page . . .