1.8.3: Viewer not maximized after returning from fullscreen

[flipflop]

XnView: MP 1.8.3 - 64 bit
OS: Linux 64bit

Maximized Viewer does not retain maximized state after returning from fullscreen

Effect: The Viewer window is non-maximized after returning from fullscreen

To reproduce:
1. Open an image in Viewer Mode
2. Maximize the window
3. Enter to Fullscreen Mode
4. Return back to Viewer mode by pressing Esc or Return key
5. The window in Viewer mode is now not maximized

Expected behaviour: The window in Viewer mode should be maximized (again)

Note: This problem only occurs between Viewer <-> Fullscreen switching. (Window stays maximized between Browser <-> Fullscreen switching)

[user0]

related
Viewer - fix unnecessary window manipulations (B)