Feature request: view full screen?

[JamesR98]

First thanks for your work on this great software! Hard to find software to view panoramic photos.

I was wondering if it would be possible to add an option to view the photo in full screen. On building straight from the git I could not find such an option and typical key shortcuts (like F11) didn't work.

Also the version number in about window still says 73.0, even though it is 74.0.

[jubalh]

I'll try to have a look.