How may I reduce/eliminate a graphics editing window?

Recently I was working in the LibreOffice word processing program, and inserted a JPG image, which I tried to edit to allow a couple of millimetres of space between the image and the wrapped text. The result was a graphics editing window which appears now to be a permanent feature of the word processing program, regardless of which document, if any, I call up; and the window obscures the text bar, and refuses to be reduced or moved. I would like to eliminate it but can’t figure out how!
Garth Spencer
Vancouver, BC

Please explain how you opened this window. Maybe you can also add a screenshot.