When I have multiple charts open in the same window and I want to switch from one to the other I just click on the tab I am interested in. However, I have found, much to my annoyance that if you don't click carefully, you can close the chart even though you didn't mean to. This has happened to me on numerous occasions. I would like to suggest that you pop an "Are you sure?" dialog when closing from the tabs or else just remove that 'x' altogether.
Thanks ... Ed.
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