For the upgrade on the last three or four builds my tabs have been deleted after the installation is completed. This is becoming quite frustrating. Unfortunately I cannot produce a debug log because it doesn't create one during installation but here are pics to show you:
You are almost there, the tabs are not deleted, but with the new installation of an upgrade, the web tab is still created, which I believe it should not do, and the last tab always take the view mode of the previous tab. For instance my third tab is set to jump to a playlist and my last tab is set to have the entire library condensed, when I upgraded my last tab was now jumping to the playlist of the third tab instead of being condensed.