[Pull-Request] Fixes and Improvements

- Fixed/Added: Verification in sheetSyncSize function, if is stretched vertically (initialized with height = 100%) , doesn't set any height.
- Fixed: Print function - when function called from not user's action, the browsers will block the popup and ask the permissions, and variable will be null.
- Added: ToggleFullScreen fly button - without menu's you can't turn off the full screen mode