Impress: how to open Slideshow in same Window?

Hello,
whenever I start a slideshow it opens in a seperate window. Previously it opened in the main window. How can I restore the previous behavior and/or switch between both modes?
Many thanks in advance,
Ulrich

(post deleted by author)

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I cannot see your dialog in its entirety, but mine seems to look different. And I already seem to have the setting you are referring to and the slideshow still opens in a seperate window.