Excellent find Stefan, your solution is much easier!
I tried that solution myself after reading your message -- my launcher was still working (in offline mode) as previously described, and it actually made the issue of the 'blank' launcher (for lack of a better term) return.
Thankfully, the F6 <tab> solution works for me to make the menu appear in the launcher. Although, its formatting is goofed up, the launch button is at least visible, I have attached another screenshot to illustrate.
Further - I thought that perhaps it has something to do with the screen resolution - I usually run 1600x1200, I reduced to 1024x768 and had the same issue - blank launcher - F6 <tab> made it work, and the launcher window also had the same results as I had at 1600x1200 (misaligned 'window' at the bottom)
My drivers are admittedly a bit outdated (nVidia), and just haven't taken the time to update them to something newer.