If one disconnects an external monitor / projector the Atom editor window has a tendency to show up outside of the screen boundaries – just as if the external monitor was still attached. It took a while to figure out how to get it back again:
- Select the Atom window (using Alt-Tab or mouse)
- Open the context menu with Alt-Space
- Select move using “m”
- Press any of the arrow keys
- The Atom window will now be possible to drag back to the main monitor using the mouse
This was mentioned in a GitHub thread here: https://github.com/atom/atom/issues/6939