Exiting from Full Screen mode incorrectly restores window size

[alabuzhev]

Version 10.0.17763.253

Start cmd.exe
Enter command mode 80, 25
Go to window menu - Properties - Layout
Check that Window Size is 80 x 25 indeed
Close Properties
Press Alt+Enter twice to enter and exit full screen
Go to window menu - Properties - Layout
Check Window Size again. This time it's not 80 x 25, but 78 x 24.

This happens because exiting full screen restores the original outer window size (with the title, borders etc., say, 802 x 532px), however:

• Entering full screen increases the buffer size (which is fine)
• Exiting full screen doesn't change the buffer size (which is also fine)
• The console window now has to display scrollbars (also fine), but since it's outer size is the same it has to display them at the expense of console viewport area.

This causes an issue in an app that automatically syncs buffer size with window size - after every switch to full screen and back window size gets smaller, the app reduces the buffer size accordingly, eventually going down to nothing.
Also, even if an app doesn't do anything like that, reducing the viewport size can make some (potentially important) information invisible.

Please consider preserving the console viewport size and increasing the outer window size to make room for scrollbars.

[boomsya]

the same bug in Far 3 when exit from full screen mode
win 10 x64 1709.16299.309