New Beta version filling window on Mac

[PegM_4]

My husband and I both installed XnView v. 0.35 on our Macs yesterday. Mine still looks normal with the regular Mac toolbar at the top and showing the red, yellow and green buttons. On my husband's Mac, he can't see these areas. To get to the toolbar, he has to move his mouse to the top of his screen then it pops down and he can access it, but he can't use the red, yellow or green buttons or resize the window from the corner (the only way to manually set the window sizes on the Mac) because they simply aren't there.

Is this part of the unstable part or is something else going on?
Thanks
Peg

[xnview]

Could you post a screenshot?