Comment 4 for bug 305558

I'm having the problem with all applications. I also have this on the laptop of my wife, she does not use it, but I changed the option, just to test it. Both computers are standard installs. Both are up to date.

So it does not depend on applications or specific computer.

The feature should work as I can set a hotkey for it. I configured it using the left windows key, called "Super L" in the screenshot. In the attached screenshot you see three applications. On the left is firefox, it is vertical maximised using the left window key. In the middle you see the dialogue to configure window preferences, the arrow is where you set the double click on title bar option. On the right you see the dialogue to configure the hot keys, an ellipse is drawn around the option to maximise vertically. The dialog on the right is also vertical maximised.

It is helpful that one can set a hotkey for it, but I would prefer to use the mouse. And the option is settable, it used to work (don't know at what time it stopped working) and it works in other window managers. It is clearly a bug and a regression..