I use spaces with the "Displays have separate Spaces" setting selected on OSX 10.10.
In this mode, OSX seems to have a "phantom space" that disappears when a monitor is unplugged, and reappears when it's plugged back in. I'd expect to have that space always exist so I can manage windows the way I want them.
Is there any way to stop this from happening?
Details:
Anytime I plug a display in, a new space is created. Then, when the screen is unplugged, a space is removed and combined with another, even if I've put windows on that new space and set it up the way I want it.
To me, the combined spaces are completely arbitrary. The space on the separate display gets combined with another space – often one I haven't used in ages – then when I plug the display back in I get two separate spaces again.
Best Answer
When you connect/remove a monitor the first space on that monitor merges with the first space on your laptop. Leave the first space on your monitor empty forever and just have a second space. The second space will become a space on your laptop when you unplug the monitor and move back to the monitor when you plug it back it.
I have two monitors and my laptop. Each monitor has an empty space as it's first space. When I plug in my dock I have to swipe to a new space on each monitor, but it avoids all the merging.