Haha, good point

To answer to Soph, 45 minutes are cutting it a bit short even from LH to LH, but it's a legal connection.
As said earlier with the new layout in Terminal 1 you can go to the Z gates without reclearing security. But you will still need to reclear immigration. Also, Frankfurt is still heavy bus boarding. I guess from MUC it's more seldom, but if you are unlucky you will need to debark your MUC flight by bus which will make loose you time. And finally, there is no room for delays of any kind. Also, consider that you might make your connection, but your bags don't.

Keep in mind: basically at the time you arrive they start the boarding for the longhaul flight. FRA-MUC is flown quite a lot per day, and if you have the possibilty try to look up an earlier FRA-MUC flight and you will be fine.

If you still opt for the 45 Minutes connection and miss your onward flight, Lufthansa will reprotect you, but that always require that there is a later flight that day, and also that space is available, so better avoiding that altogether.