Hi Axel,

re:
> One more thing fits here well: do you think it would be possible to put the
> lock/unlock function into the scene browser as well? Please teach me if I am
> wrong and the possibility to lock or unlock objects is already there.

You can use the Scene browser to do lock/unlock, it's done by holding down the Ctrl key when you click on the left-most area, where the eye icon shows for hide/show. The eye will switch to a lock for locked objects.

- Michael