Comment 3 for bug 747761

I'm not sure I understand your question.

I start without any gedit window open.

First time I double click on a file, it obviously opens a new gedit window and opens the file in it.

Then i double click on another file. Now obviously I do have a gedit window already open (in the same workspace). So it usually opens the new file in a new tab of the existing gedit window.
I repeat the same step and usually, all files are opened in new tabs of the same existing gedit window.

But at random time (this may happen even at the second file I open, or after having opened several ones), the file is opened in a new gedit window.

All this within only one workspace, with no windows (not only no gedit window, no windows at all) in any other workspace.