New Canvas opened as a tab of old window

ROOT
6

I’m puzzled, can you tell me how you create your TCanvas? From The command line?, if you type:

root [0] TCanvas c1("c1", "c1")
(TCanvas &) Name: c1 Title: c1
root [1] TCanvas c2("c2", "c2")
(TCanvas &) Name: c2 Title: c2
root [2]

You have only one window with two tabs? Maybe it’s a MacOS particularity. @couet do you know how this is possible?