Why can't I resize a window's height to make it smaller when it is at full height?

Question

I have two 21" monitors at work which I attach to my early 2011 MBP (running 10.8.1) and I move various windows between the monitors. Sometimes the windows coming down to my laptop's screen are larger than it so they fit the maximum height (but are over the maximum width) of my built-in LCD.

I can resize the width of a window by clicking its left or right edge and dragging, but when I try to resize the height, and it shows the up-arrow (or even in the corner where it shows the diagonal arrow), I can click and drag as much as I want but it doesn't resize the height, it only moves the window left and right if I move my pointer either direction.

In other words, the height is stuck when the window is the height of the screen. This only happens when the bottom of the window is at the top of the dock. When windows are smaller than the screen, resizing is fine.

Is there any way to resize a full-height window on my LCD without moving it around then dragging from another corner or something?

Answer 1

Are you running any sort of third-party window management software? That's the only reason I can think of that this wouldn't work for you.

I can resize the height of my windows using the arrows on any visible edge, including the top and bottom of a max heigh window, and the diagonals. I tested this with the Dock hidden and visible, on the side and bottom, and with a window with a size exceeding that of the screen. Worked every time.

If you're not running any third-party software that might be interfering with window resizing for some reason, the only thing that comes to mind is that your mouse is very sensitive and you're moving it slightly before the click to resize actually registers.

You might also be interested in Moom. It's a pretty handy window manager that can do things like save preset window configurations for different display set ups, or do one-click window resizing to match a specific size in pixels (which you can bind to a hotkey). It's not a solution to not being able to manually resize, but if you're moving windows around different displays often, you may find it handy. Divvy is another popular app that does some of the same tasks, but I haven't tried it myself.

Answer 2

I noticed this problem on macos Montarey and Ventura when I have a second monitor. I have my primary monitor connected via display-port on usbc, and the second monitor connected via hdmi. (using 2020 m1 mac mini). But the same problem exists if I make the hdmi monitor primary.

The primary monitor is 4k, and the secondary monitor is 1080.

To recreate the problem :

1. Make a window in any app you like that is taller than 1080 pixels on the main monitor
2. Drag it to the second monitor. The bottom of the window is "off screen".
3. Try to resize the window left or right - you can't. Try to resize the window by dragging its top - you can.

A different way to recreate the problem is to drag a window already ON the second monitor so the bottom of the window goes off the bottom of the screen. Now the horizontal resize doesn't work. Bring that window back up so the bottom isn't obscured and horizontal resizing work again.

Note that this doesn't occur on a primary display - you can horizontally stretch the same window if it's on the primary display and the bottom of the window is occluded.

The solution:

• Zoom the window on the second monitor to fill the window (not full screen) and then resize, or
• Move it back to the primary display, resize it there, then move it back.

I've reported this several times as a bug over the years but given the question was asked in 2012 and it is still behaving the same way probably means that Apple haven't got this very far up their priority list.