How do I stop Chrome window from being always on top?

Chrome suddenly started hogging the desktop. Once it is open it does not allow any other app to be on top. It is quite annoying. I researched the problem and the suggestion to use alt+space+c key works only momentarily. Other suggestions included going back to default settings, but that would erase the history (which I find very useful at times) and other settings. Is there another solution? Thanks for any ideas.